America. 91 years young and still on duty. Nightly news begins right now. Announcer from nbc news World Headquarters in new york, this is nbc nightly news with lester holt. Good evening. Its an especially busy news day, both here at home and abroad. The deadly terror attack in london just outside parliament. The attacker plowing his car into pedestrians in the citys Westminster Bridge in the shadow of big bend, turning the iconic span into a scene of carnage. Before he stormed the gates of parliament itself, leading to a deadly encounter with police and forcing lawmakers and others to race for cover. Tonight, the attacker and three others, including a police officer, are dead. At least 20 others, some of them school children, were injured. A gruesome scene in the heart of london and thats where bill neely starts our coverage. Reporter at the very heart of britains democracy, murder and terror. Dead and injured outside parliament. Tourists among hundreds running for their lives. The suspected killer and a policeman getting medical help moments after the final attack. The car he drove as a weapon still smoking. It began around 2 40 this afternoon. He had first accelerated across Westminster Bridge towards big bend, driving onto the sidewalk, zigzagging to hit people. He then headed straight for the palace of westminster crashing into railings and more people before running through parliaments gate and attacking police. Stabbing an unarmed officer. It looks like he was stabbing him repeatedly. He then somehow got up and began running forward. Reporter armed police then opened fire, crowds running as shots rang out. The shots heard by lawmakers inside. We were heading towards the voting lobbies and what we now know is i think it was three shots rang out. Reporter the attacker was voubded and disarmed. At least one knife clearly visible on the ground beside him. Yards away, a British Foreign minister now being hailed a hero tried to revive the dying policeman. Fearing another attack, Britains Parliament was in lockdown. I am now going to suspend the sitting of the house. This house is now suspended but please wait here. Reporter other lawmakers were ordered to run. High above the attack, tourists were stuck on the london eye before they were rescued and rushed away past the bridge where around 20 people lay injured, tourists among them. Buses and cars are still abandoned on Westminster Bridge. The killer driving his car across it and into parliament behind me. Armed police here still on high alert to prevent any other attack. Britains Prime Minister was evacuated. Tonight, she was somber and defiant. And we will all move forward together, never giving in to terror. Reporter and in the last few minutes, new casualty figures. Five dead, more than 40 injured. The Prime Minister also confirming there was just one attacker so a lone wolf. This attack comes exactly a year to the day since the terror attacks that killed dozens in brussels. London was shaken today. Tonight, it is calm and carrying on. Lester . Bill neely in london tonight, thank you. In todays attack, there appears to be part of a growing and troubling pattern of terrorists using vehicles as a comparatively lowtech tactic weapon to sew fear and death. What can authorities do to stop them . For more, we turn to nbcs Foreign Correspondent richard engel. Reporter todays attack in london is a new calling card for a lowtech terror strike, turning a vehicle into a battering ram followed by an armed assault. In their propaganda, both isis and al qaeda have been calling for this exact type of attack. Why . Theres little or no training required, no sophisticated weapons or traceable chemicals to acquire and no bombs that are hard to make. Ultimately, you have individuals that are literally intent of going on their own, as what seems to have happened today, and its really difficult. Reporter difficult to prevent, like this attacker who swerved into a crowd in jerusalem. The tactic has been used at least eight times since 2014. In nice, france, a driver killed 86 people with a truck on bastille day. In berlin, a man rammed a Christmas Market killing 11. And in ohio, a suspected isisinspired extremist drove onto a crowded sidewalk and came out slashing until police shot him dead. And for now, the best defense against such attacks is similarly lowtech. In new york city, the Police Department used dumptrucks filled with sand to block off access to the macys thanksgiving day parade after isis threatened a ramming attack, which never happened. The u. S. Has thousands of troops deployed overseas and spent billions on drones but they are of little use to stop a car or a knife. For that, oldfashion security seems to work best. Cops, barriers and a little luck. Lester . Richard engel, thanks. Here now to explore the challenge of preventing such attack, im joined by Senior National security analyst juan zerati. Juan, you look what happened in london. It can happen anywhere. What can be done to stop it . Lester, i think this is the new age of terror and weve got to worry about it. We have to worry about largescale attacks, coordinated attacks by Islamic State and weve seen these in europe and other parts of the world inspiring deranged individuals and radicalized followers to actually kill fellow citizens with lowtech means with high impact. I think weve got to be worried about it. Have our counterterrorism officials been able to pivot towards this new level of warfare . They have been very good at going after highend, highscale networks and cells that are trying to attack major cites. Whats more difficult is defending against attacks against soft targets, individuals who are radicalized and who decide they want to attack fellow citizens. Thats more difficult, certainly, and certainly requires a more preventive strategy that were now just adapting to. We need to get there quickly because the terrorists are adapting just as quickly. Juan zarate, appreciate your insight. Thank you. Now to the stunning new claims from the republican chair of the House Intelligence Committee who said today communications from the Trump Transition Team and possibly the president were legally and, quote, incidentally collected by u. S. Intelligence but he says theres still no evidence that president Obama Wiretapped mr. Trump, as he had claimed. And now democrats are firing back with their own bombshell. Nbcs Peter Alexander has details. Reporter tonight, President Trump says he feels vindicated. I somewhat do. I must tell you, i somewhat do. I very much appreciated the fact that they found what they found. Reporter after the republican head of the House Intelligence Committee who advised mr. Trumps Transition Team dropped this bombshell. I have seen intelligence reports that clearly show that the president elect and his team were, i guess at least monitored. Reporter none of it rebuking President Trumps claim that he was wiretapped by president obama, including from devon no nunes himself. And the fbi director. I have no information that supports those tweets. Reporter devin nunes says its not related to any Trump Campaign associates and not picked up through surveillance directed at mr. Trump or his aides. What he says is alarming that the names of some trump team members may have been i am pormproperly revealed or unmasked. Outraged nunes went to the president before briefing him. The chairman will need to decide whether he is the chairman of an independent investigation into conduct or he is going to act as a surrogate of the white house because he cannot do both. Reporter nunes defiant. Why is it appropriate for you to brief President Trump as hes part of the investigation . The president needs to know these intelligence reports are out there. Theres a Justice Department investigation and hes throwing a lifeline by the chairman of the House Intelligence Committee. Reporter tonight, the House Intelligence Committee top democrat is amping up the stakes telling nbc news theres more than circumstantial evidence of collusion between russian operatives and President Trump. And theres more drama in washington. A day before the critical vote in the house on the gop obamacare replacement. Tonight, more republicans say they are going to vote no but the white house says this is the bill and there is no plan b. Not to be forgotten in all of this, millions of americans wondering whats going to happen to their health care. Nbcs Hallie Jackson has that story. Reporter for a white house built on winning, its first loss could be 24 hours away with the Health Care Bill on life support. We believe we need to postpone the vote and get it right. Reporter republicans looking for symbolism, instead find themselveses scrambling to win over voters from the conservative Freedom Caucus, a bloc mostly against the bill. Do you think you have enough to tank this thing . I dont think. Reporter you know . Yeah. Reporter right now, our nbc News Analysis shows 28 House Republicans will probably vote no. Six would have to flip or the bills dead since no democrats are on board. Instead, led by the former Vice President , they are rallying in resistance. I aint going anywhere. This is not going to pass. Reporter for the gop, a delay could be embarrassing but failure altogether devastating. I think the better, smarter move would be to step back, reconfigure the Playing Field a little bit, crap that is in the way that is palatable to house conservatives and senate moderates. Reporter a senior gop aide tells nbc news they have no plans to push back the vote set, for now, for tomorrow. Were adding votes by the day. Were not losing votes. Were adding votes and we feel like were getting really, really close. Reporter close wont cut it with the white house refusing to even acknowledge the possibility of defeat. Theres plan a and plan a. Were going to get this done. Reporter what does it say to you if the president cant get this done this week . This is really a defeat of paul ryan and paul ryan will have to come to conservatives now and ask us what we want. Reporter even as late as tonight, the white house is considering a concession on Insurance Regulations with one Freedom Caucus store saying they are couch shausly optimistic about it. Members are set to come here tomorrow as the president works to seal the deal. Lester . All right, Hallie Jackson, thank you. Also in washington, day three before the Senate Judiciary committee for Supreme Court nominee neil gorsuch. He promised to be an independent of the president who nominated him and amid praise from republicans, gorsuch deflected attempts by frustrated democrats to get him to wade into certain legal and political issues. And with no stumbles in the hearings, gorsuch appears headed for confirmation in early april. Tonight, theres new information connected to the Electronics Ban affecting passengers on certain flights coming into the united states. Tonight, nbc news is learning some of the reasons the new ban on board was put in place by the u. S. And then britain. As nbcs Miguel Almaguer reports, isis and al qaeda may be working together. Reporter tonight, a senior Law Enforcement official tells nbc news isis may be getting help from al qaeda. A Disturbing Development following the new Electronics Ban. It affects flights into the u. S. From eight majority muslim countries and was ordered after intelligence discovered isis operatives sought to plant explosives in laptops and other electronics. I think what you have is two different groups that compete with each other but both of which had the same mission, to shock the world by bringing down an international airliner. Reporter calling the intelligence extremely sensitive, Security Officials would not confirm if isis was developing an explosive that could be hidden in a laptop, similar to the attack that blew a hole in this plane last year over somalia. The new policy to be implemented by saturday restricts electronics larger than a smartphone from the cabin. It becomes much more difficult to carry out a successful attack if the device is not located on the person of the individual carrying out the attack. Reporter officials have long feared al qaedas master bomb maker, ibrahim al asiri, who helped develop the underwear bomb, may be sharing his trade secrets. For now, the ban affects ten airports, some 50 flights a day. Some say the new policy could change the way we all fly in the future. With those 50 affected flights arriving here in the u. S. Every day affected by the Electronics Ban, some are wondering why is it only be implementing at ten airports. In fact, Security Experts tell us tonight for the ban to be truly effective, it may need to be rolled out at airports worldwide. Lester . Miguel almaguer, thank you. Still ahead, the desperate plea for help. A harrowing 911 call made from a 9yearold girl from the seat of a moving suv as their mother put their lives in danger behind the wheel. Also, the inspiring story of a nurse proving age is can i get some help. Watch his head. Im so happy. Whatever they went through, they went through together. Welcome guys. Life well planned. See what a Raymond JamesFinancial Advisor can do for you. Hi hey you look good. Thank you, i feel good. It all starts with eating right. Thats why i eat amaz n prunes now. Theyre delicious and help keep my body in balance. I love these. Sunsweet amaz n prunes, the feel good fruit. For my constipation, i switch laxatives. Ed stimulant laxatives make your body go by forcefully stimulating the nerves in your colon. Miralax is different. It works with the water in your body to hydrate and soften. Unblocking your system naturally. Miralax. They carry your fans shpassions, hopes, and dreams. S. And maybe, a chance at greatness because shoulders were made for greatness. Not dandruff. But when we brought our daughter home, that was it. Now i have nicoderm cq. The nicoderm cq patch with unique extended release Technology Helps prevent your urge to smoke all day. Its the best thing that ever happened to me. Every great why needs a great how. Shell unease you all the better just to please you shes precocious, and she knows just what it takes to make a pro blush all the boys think shes a spy, shes got bette davis eyes back now with a harrowing call for help from a brave 9yearold girl. She dialed 911 from the back seat of an suv while her mother was allegedly driving high on heroin. Nbcs blake mccoy with details. Where are you at . I dont know. I cant read theres a sign and i cant read that far. Okay. Reporter a terrified 9yearold girl desperate for help. Now were parked somewhere he a i dont know where. Im going to get you help. Reporter that 911 call made from the back of this suv in cincinnati. In the front seat, the girls father passed out from a suspected heroin overdose. Her mother, fading in and out of consciousness behind the wheel. Theyre both breathing. Okay. But youre unable to wake them up . No. I tried and they wont wake up. She said, grandma, i put that car in park myself. I stopped the car. She saved two lives and her own. Im so proud of her. Reporter charges against both parents include child enda endangerment. Last year, a frustrated Police Department showed these photos of how kids are becoming victims of ohios opioid epidemic. In 2015, 2934 children were taken into state custody because of abuse. Some wont ever see their parents again. Like the kids who found this koubl, a Spirit Airlines pilot and his wife dead in their centerville home last week. The girl from this latest 911 call is unharmed but tonight a sobering reminder just dont hang up. Okay. Reporter addictions toll is felt far beyond the addicts themselves. Im scared. I know youre scared but youll be okay. Reporter blake mccoy, nbc news. A heartbreaking story. Well be back in a [ ominous music ] [ sniffs ] little girl daddy trapped by your unrelenting nasal allergies . [ meow ] [ sneezes ] try clarispray clarispray provides unsurpassed relief. Its 24 hour, nondrowsy and prescription strength. Free yourself with clarispray, from the makers of claritin. Ques. Are my teeth yellow . Have you tried the tissue test . The what . Tissue test hold this up to your teeth. Ugh yellow. I dont get it. I use whitening toothpaste. What do you use . Crest whitestrips you should try them whitening toothpaste only works on the surface. But crest whitestrips safely work below the enamel surface. To whiten 25x better than a leading whitening toothpaste you used the whitestrips i passed the tissue test. Oh yeah. Would you pass the tissue test . See for yourself with crest whitestrips. They are the way to whiten. Dont let the food you eat during the day haunt you at night. Nexium 24hr. Shuts down your stomachs active a