>> reporter: he captured video moments after police say a man was stabbed. >> we just saw a guy laying on the ground. >> reporter: he and his friends looked out from the barnes & noble parking lot. >> we heard him screaming. >> witnesses say it appears he was stabbed in his upper body. >> someone said he was walking the street with blood all over him so he went to the grass and people were warming him up. and then the first couple police cars showed up. >> reporter: the teenagers say other drivers stopped and helped him before the ambulance arrived. >> crime scene investigators marked up close. detectives searched for clues. witnesses say a woman and a golden retriever were also in the honda. when police arrived they took another car away from the scene. the suspect vehicle was already gone. >> reporter: police say the victim is a 30-year-old man from randolph. he's in the hospital and police have yet to make an arrest in this case. reporting live in braintree, cbs news. an explosion in north andover rocking the dow chemical plant and badly injuring several workers. in the past hours, investigators held a news conference. >> we learned the chemical responsible is something called trimethylaluminum . it's a key ingredient in making led lights like these, so it's very useful but also quite volatile. so much so that hazmat teams still at this hour have not been able to get into the actual laboratory where the explosion happened. >> due to the condition of the building the continue operation -- continued operation of our the actual laboratory. >> reporter: teams of investigators working into the night, trying to learn more about this powerful explosion. blessed so strong, neighbors felt it around 2:30 thursday afternoon. >> the house should have -- shook a little bit and my dog went crazy. >> reporter: this is the home to the dow chemical facility. >> this was a chemical that was reactive to water and for some reason that will come out as part of the investigation, this chemical reacted with water, which resulted in the explosion. >> reporter: four workers had to be rushed to the hospital, with serious injuries. three of them so severe, they had to be flown by medical helicopters to hospitals in boston. the four victims state here, all of them critically injured. >> reporter: they had blast injuries from the pressure of the explosion as well as the chemical on their body that they were exposed to and burns as well. at this facility. back in 2013 another explosion killed a worker but now the state fire marshal says the two blasts are not related. >> it was a different type of chemical an operation that resulted in that incident. >> reporter: in addition to the four people who remain hospitalized tonight, we just learned there was actually a fifth person injured in this afternoons explosion. that persons injuries were relatively minor, so they were allowed to go home. you can see behind me cruiser packing up for the night, but they will be back here this -- first thing tomorrow. they have more investigating to do, including getting into the laboratory. jim armstrong, cbs news. >> dow chemical rates our thoughts and prayers are with the family friends and colleagues during this time. an investigation is underway to incident. and we're learning that two people are under arrest tonight on terror related charges in california and texas. investigators say a sacramento man travel to syria to fight alongside isis and then lied to authorities about it. the other arrest in texas tonight where the lieutenant governor says that arrest may have prevented an attack. and more breaking news, state police taking down a man who led them on a chase from -- all the way to middleborough. they say the man threatened to harm others and thought he was armed. once he came to a stop, troopers found a fake handgun inside the car. looking live it downtown boston tonight, beware of black ice. there could be slippery spots on the roadways. >> but a warm up is on the way. eric fisher is here. eric? a chilly night again here, that's the case all this week. outside, a wide range of temperatures. the low spots where the wind isn't blowing -- we will be watching for tomorrow morning the wind turning northeast of starting to bring in low clouds and drizzle. just enough moisture that could freeze on contact in some areas, especially in north and west boston. so tomorrow morning very light drizzle, maybe a thin glaze. those clouds will tend to expand as we head through the day tomorrow. -- after a crash that killed one man and left the other paralyzed. >> it was my worst nightmare come true. >> tonight his fiancie is months before their wedding. >> garrett fitzgerald was in the car with three other agents when he driver crashed into them head-on. julie is in the studio now. julie, with his and five -- his fiancis inspiring message. >> this couple has frankly no idea what the future may hold, and yet they are incredibly grateful. >> i picked up the phone and it was my worst nightmare come true. >> just three days before the new year, life forever changed for joan while -- jill lyall. >> it was garrett saying that there was an accident and that i was the best thing that ever loved me. >> i knew i had to get to him. he said he couldn't feel his legs. >> a secret service agent on the job for just months was one of four agents injured when new hampshire. his smile. and his eyes. and he says hey babe and i knew we would find a way to get through it. >> four days he could feel nothing below his shoulders. >> he is regaining, every day he's doing a little bit more, moving his right arm which is really exciting. little victories. >> the little things are now all big things. >> our world might take a different path, but it's still him and i together. >> reporter: and in a week and a half, joan has learned only a few things really man -- really matter. there march wedding is still on although it might be delayed and when the day does come there will only be one thing. >> he is and always will be the best person that i've ever met. he inspires me. >> reporter: this couple has been together for nine years. even if it's not the big wedding she had planned, joan says it will truly be her dream julie loncich, wcb -- wbz news. >> trading has been up down in all over the place. but today the dow plunged 392 points. liam martin -- liam our 401(k). >> you would want to look at that 401(k) today, it capped year on record. >> those smiles at the opening turned to concern. the dow plummeted hundreds of points within seconds, nearly 400 points by day's end. that concern stems from major losses in china. the shanghai stock market has had to be shut down twice this week to stitch bear selloffs. -- bigger selloffs. global growth for most of the last decade. >> reporter: the uncertainty of that global driver is prompting a 900 point loss this week in the dow. >> take your time when it comes to investing. don't overreact. >> financial advisor david caruso says the average american with a 401(k) should not be panicking. >> when you look at this market fluctuation, the way that it has gone over the last three or four days, it usually is an overreaction to something that's happening, and they tend to go away. >> as for china, many experts expect their economy to continue to struggle in the months ahead./keep oil prices down and could lead to further stock losses here in the us. as for the us economy itself many forecasters expect stable growth in the months ahead. david? >> liam thank you. the president took to the airwaves for a live town hall meeting answering questions about the control. the president of course recently took executive action to expand background checks. fbi to complete checks efficiently. bill evans was invited to the scene since -- cnn special. the president says he's committed to the second amendment but wants to make sure guns are in the hands of responsible owners. >> if we can combine gun safety with sensible background checks and smother steps, we're not going to eliminate gun violence, but we will lessen it. >> the president writes that he will not vote for any candidate even a democrat who does not support what he calls commonsense gun reform. we set? big dreams just got bigger. nobody one last night strike so saturday's jack bought is a record-breaking $700 million. there is a $1 million manner -- winner somewhere in plymouth. that winter has not come forward yet. there is a 17 percent chance that nobody will win saturday's drawing. that will raise the jackpot -- to $1 billion. massachusetts is cashing in and that is our number of the night. 12 points explain dollars. that's how much money -- $12.6 million. that's how much money massachusetts has raised since the jackpot began. donald trump on the attack unleashing a new attack. >> and how hillary clinton is using her husband to try to derail -- how trump is using hillary clinton's husbands pass to try to derail her campaign. beyonce joining the is the economy rigged? well, the 15 richest americans acquired more wealth in two years than the bottom 100 million people combined. i'm bernie sanders, and i approve this message. my plan -- make wall street banks and the ultra-rich pay their fair share of taxes, provide living wages for working people, ensure equal pay for women. the middle class will continue to disappear unless we level the playing field. with your help, as president, campaign 2016 tonight. take a look at the crowd of trump in vermont tonight. >> the gop front runner is launching a new attack ad against hillary clinton. >> it is using bill clinton's past to attack her campaign. jon keller joins us now. what's the strategy here? >>this is a game plan right out of the bill belichick playbook. take away your opponent's best weapons. force them to respond to you. punch them right in the mouth. it works on the football field. tenet put trump in the white house? -- tenet put trump in the white house >> what are anthony weiner and bill cosby doing in a campaign ad? >>they costar in a new trump wed ad mocking hillary clinton's core asset, her advocacy for women and trump once again uses the checkered past the former president bill clinton as a weapon against her. >> women's rights, our human rights -- >> i don't have any response. iowa bill clinton refused to engage in -- with trump, a strategy his wife has already endorsed. >> i will let him live in his alternative reality and i'm not going to respond. >> but it was too -- it was hillary who taunted trump by telling an iowa newspaper he had a penchant for sexism. >> i hit her back and i talked about her husband on the abuse of women. it's tremendous abuse. >> and now this -- it's a tactic that excites gop voters who about were both clintons and helps diminish -- pretending a clinton trap showdown is rt -- trump showdown is rt and -- already underway. >> once and for all, let's keep fighting for opportunity and dignity. >> trump's led -- blunt recycling of the old scandals may have other consequences for weak among younger women so far. once again the master of reality tv showing his showbiz skill set is a nice fit with our over caffeinated, dirt hungry campaign culture. david? >> nice description. thank you. to a dairy wreck you -- rescue operation in the deep assaulted in america. -- salt mine in america. they are finally back on solid ground tonight. they were beginning their shift last night when the elevator carrying them got stuck. all 17 were pulled to safety and believe it or not none of them was hurt. >> and new dash cam video tonight showing a florida woman begging for help as officers tried to arrest her for refusing to leave the hospital. in the video she tells police that she can't breathe and she's going to die. police thought she was faking. the woman did later died. that a laboratory the -- a lamborghini -- the driver of this white sports car driving right through the water. not advised. right now the storms are causing flooding and big problems on california roads. is that something you would do with a $200,000 car? >> i wouldn't do it with a $2000 car. i'm afraid i would get stuck there. >> don't do it in a pickup for a lamborghini, chevy, a ford. we hate to see that as floodwaters. terrible thing to do. california's getting a breather right now but the next room is lined up here. this one will be focused more towards central and northern california and less on southern california. meanwhile we have our own issues on this coast, a big storm system off to our south and east. this could get a name as a subtropical system, the first one of the season and its name would be system -- would be alex. we've been living on the fringe providing a purchase sunset this evening. look at these gentle winter hues . these are the readings we will wake up to tomorrow morning, very cold temperatures. if you're up early there is a space station flyby at 5:16 a.m. you also notice that venus is out there very bright and saturn close by so a lot to catch if you are one of those early risers. if you're at that hour, probably not getting too much sleep tonight. clouds start to increase especially over boston and just enough moisture in the air that there could be a few areas that are slick with black ice. i think it will be few and far between but something to be cautious with during the morning. clouds will fill in as we head into the afternoon. eventually massachusetts -- eastern massachusetts getting in on that cloud cover. stayed chilly across much of the interior. around 40 degrees right along the coastline and for southeastern massachusetts, so we wouldn't expect icing there. again a chance for a couple slick spots in the morning. a better chance for a little bit of that freezing drizzle as we head into friday night and saturday morning and during the day on saturday we might even get a couple of spare snowflakes. again all this is very light, just have to mention it because it could cause slick areas. tomorrow a bigger storm system moves its way off to the north and east. this is a warm storm meaning it's already -- heavy rain at that and maybe even a few thunderstorms as it passes on sunday. highest totals could be as high as 2" of rain and for a few hours it brings in warm air. we spike in the 50s and should be very close to record highs. the bad news here, that rain goes all the way through northern new england as temperatures rise around 40 degrees on sunday. we'll get into that rainfall on sunday. looking for snow on the seven- day and here's the acura forecast. a chilly day with shot -- was falling temperatures, wednesday the storm will be deepening to our east and maybe close enough to bring a snowflakes which have been elusive so far. a big media shake up here in boston. nbc is announcing it will pull its affiliation with channel 7. the network will launch a new station nbc boston on january 1 nbc boston on january 1, 2017. it will go over the air on channel 60 which is currently telemundo. whdh has been in and -- nbc affiliate for 20 years. whdh is taking it to court. gronk speak plans -- dear fellow citizen, i know what it' s like to buy a house. i know how it feels to be stressed about money. because i' m not just a fellow dad, fellow mom, fellow saver, m a fellow citizen. her best. just like you. elizabeth trackler samantha parke robert kennedy jared duemling one of these nights we will be able to say this was a great night for the celtics. >> i think we thought they'd be better than they are. >> it's a funk they are in right now. let's start with those celtics in chicago tonight. brad stevens flew to indiana to be with one of his former butler players who is battling cancer. assistant jay guernica filled in. of the gate. the celtics were up by 6 after one and they jumped out to a 10 point lead in the second quarter but the bulls went on a 10-0 run of their own. jimmy butler found the hoop and the power -- the foul, 19 points, 10 assists and they lead by one of the half. things went downhill from there. derrick rose and gasol combined -- rose had 18 himself and the celtics lose for the second night in the row, -- in a row. tom brady and the patriots had another walk-through today, number 12 looking even more comfortable jogging then he did yesterday. the pats are enjoying it by this weekend rob gronkowski plans to watch the wild-card games on tv. >> it's great to sit back whenever i can. ' little sports drink -- no pop or soda. >> no pats game this weekend but we still have all access tomorrow night at 7:00 on the bbc. among the highlights sitting down with bill belichick. and we will update the playoff picture with patriots game day. college hoops, bc hosting notre dame. he has 15 points and 11 boards for the fighting irish. his ninth double double of the year. the eagles lose 82-54 to follow -- fall -- it was so bad that after the game christian apologized saying that's not how our teams play. this was all huskies, junior 15 points and 11 rebounds. they improve to 11-5 overall. college hockey bu at number five harvard and what a comeback win for the terriers. scoring three goals in the final four minutes. the game-winner at only 1:49 to play. harvard falls to 8-to-3. and the broncos announcing peyton manning will start in the divisional round. they said osweiler has an mcl sprain in his knee. superstars teaming up to the super bowl halftime show. >> we will tell you who else would join beyonci on stage days after the paris attacks, top-secret briefing on the terrorist threat... marco rubio was missing - fundraising in california instead. two weeks later, in san bernardino... and where was marco? fundraising again in new orleans. over the last 3 years, rubio has missed important national security hearings and missed more total votes than any other senator. politics first: that's the rubio way. right to rise usa is responsible for the content of this message. new england's energy comes from a pool of energy producers. eversource buys it at a set market price and delivers it to you. but that pool is shrinking, causing energy supply rates to go up and down. to increase our natural gas supply and bring in affordable, clean hydropower from canada. we're leading the way toward the solution... because more energy means lower energy supply rates for you. ever new england. eversource. what would you do with five minutes to kill, and a smart phone? check the scores. probably post a pic. text a friend. how about register to vote? really? you can. five minutes online and a massachusetts drivers license is all it takes to register so you can vote for our next president. go to registertovotema.com. it's that easy. done. i just registered. that was easy. if you weren't super excited about seeing coldplay perform in the halftime show, we learned they have a guest helping them out. >> make way for beyonci. >> pepsi is confirming tonight that beyonci will perform with coldplay next month in santa clara california and levi's stadium. you can see beyonci in super bowl l right here on february 7. than the bottom 100 million people combined. i'm bernie sanders, and i approve this message. my plan -- pay their fair share of taxes, provide living wages for working people, ensure equal pay for women. the middle class unless we level the playing field. with your help, as president, not a bad way to end the the clouds building and not