Reporting tonight, lester holt. Good evening. With a shooter of two Police Officers still out there, every nightfall brings growing anxiety to the streets of ferguson, missouri. Ferguson already is in upheaval amid cries for change and the abrupt firing of officials including the chief of police. The shooting yesterday morning came as the city was still grappling with how to fully respond to that Justice Department report which found a pattern of police bias towards the citys poor and minority residents. In a moment my conversation with the mayor of ferguson and his answer to those who want him to step down. But lets begin here with ron allen in ferguson. Reporter for a second day a huge police manhunt. An exhaustive search for a gunman accused of targeting a line of police at that demonstration this week. I cannot tell you at this point that an arrest is imminent. Theres certainly nobody in custody. Reporter the two wounded officers recovering at home today, one with a bullet still lodged behind his ear. President obama spoke out last night. Whoever fired those shots shouldnt detract from the issue. Theyre criminals. Reporter overnight protesters and now Missouri State and st. Louis county police kept their distance. Hands up dont shoot reporter among the demands dismantle the entire Ferguson Police force. Others want the mayor gone. Since the Justice Department began investigating ferguson, six city employees, the police chief, city manager have left. Every Police Officer has had mandatory diversity training. And Court Reforms are underway. Some fees and fines eliminated, seen as targeting the poor. Leslie bell sees himself as the kind of change ferguson needs. The son of a cop and himself a law professor. Hes one of four africanamerican candidates for city council in april. Seeking to push the number up from just one. How important is it there be more diversity on the council . I think its very important. I think when we work together, when we get to know one another we reach better understandings. Reporter through it all a High School Senior with offers from universities like howard and morehouse still sees his future here. You would . The movement will always live. This is not a moment. This is a movement. Ferguson is a movement. Reporter tonight he says hell be out there marching in the streets. Adding to the tension Police Investigating the ambush that happened out here say its still unclear whether the gunman was someone involved with the protest or an outside age tater as demands continue for a complete overhaul of the city of ferguson. Lester. All right, ron. Thank you. Before we came on the air this evening i spoke with ferguson mayor james knowles. I began by asking him about the emotional climate in his city right now. Well, you know, weve gone through a lot over the last six or seven months. And weve been working very hard to try to bring this community together. I think unfortunately the events of the other night is going to start hopefully, unfortunately, i think, create a climate that is going to be difficult to get past. Has this shaken your resolve to stay in Office Despite the many calls for your resignation . No, i mean, i get continued support from a lot of residents. You know i hear it from phone calls, emails, facebook people who want me to stay in office. I mean, obviously theres always going to be people who are against you. And those people have been vocal out there. But, you know, theres ways for them to remove me if they so choose. Do you agree with the conclusion that there was a pattern of bias within the Police Department . I dont think that the individual officers were out there looking to affect africanamericans any differently than they were white americans. I think you probably weve seen that theres been some bad apples out there. I think that but i dont think that that is indicative of the entire Police Department. You said you dont want to resign. Would you embrace a recall election to put this behind you once and for all . I think thats just another setback for the community. I mean, if thats what a majority of the community wants, then thats fine. Unfortunately, the events of the other night only serve to divide the community. A recall election will only serve to divide the community. But if that is the will of the people, then so be it. But right now im focused on moving this community forward. My conversation earlier with ferguson mayor james knowles. Tonight, a salvage operation is underway at the site of that black hawk Helicopter Crash off florida that killed 11 u. S. Service members. Seven of those killed were u. S. Marines, and they were identified today. Our report tonight from nbcs mark potter. Reporter a salvage barge hired by the u. S. Army arrived at the crash scene early this afternoon and didnt take long before it began pulling up the twisted wreckage of the downed black hawk helicopter from santa rosa bay. First to be seen the blades of the chopper. Complicating the recovery is that the bodies of two members of the Louisiana National guard flight crew were still trapped inside. Today, the u. S. Marine corps released the names of its seven special Operations Combat veterans who died in the tuesday night training accident. They include Master SergeantThomas Saunders from williamsburg, virginia who served in kosovo, afghanistan and iraq. And Staff Sergeants marcus bawol and trevor blaylock, both from michigan. Our thoughts and prayers with the marines, soldiers, their family and friends as we all mourn that tragic loss of life. Reporter also killed in the accident Staff Sergeant andrew seif from holland, michigan. He was the 2013 marine of the year and was just recently awarded the silver star the millarys third highest decoration for valor. Captain Stanford Shaw from new jersey was his High School Student government president and served two tours of duty in iraq. And Staff Sergeant kerry kemp from washington, and Staff Sergeant flynn from queens new york, both decorated from combat service and proud fathers of baby girls. The names of the four army victims have not yet been released. And as you can see out there in the distance, the salvage efforts to raise that chopper is still underway. In fact, moments ago they brought a big piece of that chopper and put it on that barge. This effort is expected to go into the night weather permitting. Lester. Mark potter tonight. Thank you, mark. A newly hired attorney for the fraternity kicked off the university of oklahoma campus as some members are receiving death threats. Now the chapter is considering suing the school in a bid to unsully its name after some members were caught on tape chanting racial slurs. We get a lot more now from nbcs Gabe Gutierrez whos on the campus. Reporter for days the racist chant has been widely condemned. Today the university of oklahoma Sigma Alpha Epsilon chapter fought back. We need to avoid a rush to judgment. Reporter its alumni have hired highprofile Attorney Stephen Jones who represented Timothy Mcveigh in the Oklahoma City bombing trial. After the video became public, University President david boren quickly denounced the fraternity. Real sooners are not bigots. Theyre not racists. There is zero tolerance for this kind of racist and bigoted behavior. We dont want to be defined by those who completely violate our values. Reporter some experts question whether a Public Institution expelling the two students is legal. The First Amendment protects all ideas, including really evil ideas. Reporter saes National Headquarters says it supports the stance that ou has taken and its moving forward with the plans to revoke the membership of all suspended members here permanently. Saes under fire across the country. Its headquarters is investigating allegations of racism including at Louisiana Tech university. The sentiment that it may be embedded in National Oration is just absurd. Reporter but members like mikhail psychs in mississippi say thats not what sae represents. The easy thing to do is to judge a Large Population by the actions of a few. Reporter tonight at ou the local sae chapter is not ruling out a lawsuit at the outreach from this video stretches on. Gabe gutierrez, nbc news, norman, oklahoma. Weve gathered new information about the car crash at the white house involving two secret Service Agents allegedly after a night of drinking. Weve learned the president wasnt told about it until quite long after the fact. Now some lawmakers are questioning the leadership of director Joseph Clancy who was brought in to restore the agencys reputation. We get more on it from nbcs kristen welker. Reporter it took five days for president obama to be told that two top secret Service Agents, Mark Connolly and george ogilvie, allegedly drove into an active bomb investigation outside the white house last wednesday. Theres absolutely no excuse for any delay with a breach this serious on the white house grounds themselves. Reporter the Congressional Committee that overseas the service is demanding answers from director Joseph Clancy next week. Including why an unnamed supervisor allegedly allowed the two agents to go home without undergoing field sobriety testing, as was recommended by other officers at the scene. The two senior agents have been reassigned and have not responded to requests for comment. These instances are starting to pile up and starting to have a cumulative effect on morale. Reporter clancy a 27year secret service veteran, was tapped to lead the agency after a series of embarrassing incidents including last years fence jumper who forced his way all the way inside the white house. Can he make the tough decisions with people who have been his colleagues for 20, 30 years or can he not . And so this is going to be his big test. Reporter and today the man who jumped over this fence last september, omar gonzalez, pleaded guilty to two federal charges. Hell be sentenced in june. Kristen welker, nbc news, the white house. Well, the big thaw that many of us have hoped for is finally under way, except it means flood advisories are in effect tonight from mississippi to new york as frozen waterways begin to melt. On land theres another hazard as millions of motorists are finding out. We get more on this tonight from nbcs ron mott. Reporter in the middle of lake erie, the coast guard is slicing through thick ice to prevent flooding the three large rivers there. Thickest ice we encountered today was probably approximately 20 feet above the surface of the lake and 15 feet below the surface of the lake. Reporter near cleveland its too late. It came inside my house about three feet in my house. Reporter some ohio rivers are spilling onto streets. Millions of people from buffalo to biloxi are under flood advisories. And here in boston closing in on an alltime record for snow, giant dirty piles like that are reminders of a tough winter. But now that most of it has melted off the roads, new hazards have emerged. Potholes. They come in all sizes from mere bumps to bonejarring jolts. And it can be a pain in the wallet, too. Business is picking up at gary sacks tire shop. Broken rims, suspension issues, exhaust issues from bottoming out. Reporter the cost of potholes . 6. 4 billion last year alone. Back in cleveland the pothole killer is on the loose. A onestop patch shop. 90 seconds from start to finish. Near baltimore along busy i95, 100 potholes a night are being filled as temperatures warm up. Out west potentially record heat for Southern California into the 90s. Were gearing up for a big weekend this weekend. Reporter technically still a week of winter left. Ron mott, nbc news, boston. Overseas now, there is no shortage of controversy surrounding Vladimir Putin. The crisis in ukraine, a crumbling economy, the recent murder of a top dissident. Now add to all that a mystery. He hasnt been seen publicly for more than a week. Where is he . Nbcs keir simmons is on the hunt. Reporter this is the last time Vladimir Putin was seen in public, last thursday with italys prime minister. A planned visit to kazakhstan this week was canceled without explanation. Trending today the hashtag whereisputin. He likes to flaunt his health, famously appearing shirtless on horseback. Has the 62yearold leader fallen ill . Theres absolutely no reason for doubt about the state of his health. His health is really perfect and everything is okay with him. Reporter the kremlins own website has been reportedly misleading showing putin in a meeting it said happened wednesday when really it took place a week earlier. The president s vanishing act has triggered some wild speculation that he went to switzerland for the birth of his girlfriends baby. Some ukrainian children even drew pictures of the russian president abducted by aliens. It all reminds some people of the soviet era when kremlinologists searched for clues about public appearances. Today, friday the 13th, the kremlin released pictures of putin it said were taken today. But doubters pointed out the meeting was not public and not shown live. Privately u. S. Officials tell nbc news putin may be under the weather. The mystery may be solved monday in st. Petersburg where putin is due to appear in public. Keir simmons, nbc news, london. Pope francis marked this second anniversary of his election today with the prediction about his tenure. The pope celebrated mass at st. Peters basilica and also heard confessions from the faithful. In an interview he said he thinks his time as pope will be short, perhaps four or five years. He also said that while he doesnt mind being pope, he misses going out in rome unrecognized for a pizza. Still ahead tonight, they cant make it on their own. But suddenly theyre washing up onshore faster than rescuers can get to them. Also, the island too new to appear on any map which no one has set foot on until now. Were back with a rescue mission thats becoming increasingly urgent as more and more sea lions are washing ashore in Southern California. Many of them hungry and sick. Our report tonight from nbcs hallie jackson. Reporter Peter Wallers team scoops up another starving sea lion today. This is skinny for a sea lion. Yes, very skinny. Probably 50, 60 pounds light. Reporter one of hundreds of pups hes helped so far this season. Its kind of overwhelming. Were going all day. Calls at 3 00 in the morning, 4 00 in the morning. Reporter the pups are washing up onshore in record breaking numbers, emaciated and dehydrated. Like lucy who looked like this when she was rescued and now looks like this. Typically about 60 sea lions are stranded in california in january and february. This year its skyrocketed to more than 1,200. This is the most sea lions ive rescued in 30 years. Reporter its gotten so bad sea world announced this week its suspending its sea lion show so trainers can help with rescue missions, which can get emotional. This week as i see the commitment every day. Reporter the sea lion pups usually stay on the Channel Islands off californias coast, but scientists think warmer waters forcing their mothers deeper into the ocean to look for food leaving the babies to fend for themselves. They ended up on our beaches skinny and cold and looking for space. Reporter problem is rehab facilities are filling up too fast. The sickest and weakest nursed back to help at shelters. And eventually, hopefully, released back into the wild. Thats the First Priority for rescuers. And for the pups a Second Chance for survival. Hallie jackson, nbc news, santa monica. Heres to those coming to their rescue. When we come back no time to waste. Skiers dig through the snow to find a friend trapped under an avalanche. There is a brand new island in the South Pacific never before touched by man until now. Heres some pictures taken by a team that is believed to be the first to set foot on the new land formation, which was created only months ago by eruptions from an underwater volcano. Its considered very unstable though, and may not Stay Together for long. From europe scenes of a dramatic rescue after an australian skier became trapped in an avalanche. It was all captured by a gopro camera worn by one of his friends. There was a frantic search. Then, once located, the frantic effort to dig him out of the snow. The trapped skier described a wall of powder and said he thought he was going to die. He was buried for about an hour until his friends finally reached him and brought him out of the snow alive. Anyone whos taken a walk down the aisle knows weddings dont come cheap. According to the wedding website, the knot the average cost last year was more than 31,000. Thats a new alltime high. The least expensive place to get married, utah around 15,000. The most expensive, not surprisingly, right here in manhattan. But listen to this number. 76,000 for a manhattan wedding. Honeymoon not included.