Jared Wickerham/APOvernight DevelopmentsBoston Marathon Bombers Sought in Pre-Dawn Manhunt (PHOTOS)One marathon suspect was killed in an overnight shootout, while another is at large. See photos of Boston cops combing the city.04.19.13 6:58 AM ETJared Wickerham/APShannon Stapleton/Reuters, via Landov People wave flags and celebrate the arrest of the second suspect, Dzhokhar Tsarnaev, in the Boston Marathon bombing. Matt Rourke/AP Police officers smile to fellow officers as they leave the scene after the arrest of the second suspect. Jared Wickerham/AP Spectators clap and cheer while law enforcement members leave the scene near Franklin Street, in Watertown, MA. Matt Rourke/AP Police officers guard the entrance to Franklin street where during an active crime scene search for the suspect in the Boston Marathon bombings. Boston Globe via Getty SWAT teams conduct house to house searches in an area near the shootout that took place the previous evening. Allison Shelley/Getty In Montgomery Village, Maryland, Ruslan Tsarni, uncle of the suspected Boston Marathon bombing suspects, spoke to reporters in front of his home. Tsarni asked the still-at-large bombing suspect, Dzhokhar Tsarnaev, to turn himself in. Charles Krupa/APPolice in tactical gear surround an apartment building while looking for a suspect in the Boston Marathon bombings in Watertown, Massachusetts, Friday, April 19, 2013. The bombs that blew up seconds apart near the finish line of the Boston Marathon left the streets spattered with blood and glass, and gaping questions of who chose to attack and why. Matthew Healey/UPI, via Landov Massachusetts State Police search the backpack of a bystander on Arsenal Street in Watertown, Massachusetts, during a massive manhunt for one of the two Boston Marathon bombing suspects, on April 19, 2013. The man was later cleared. Charles Krupa/APPolice in tactical gear arrive on an armored police vehicle as they surround an apartment building while looking for a suspect in the Boston Marathon bombings. Jessica Rinaldi/Reuters, via LandovSWAT officers go to a door with guns ready as they search a suburban neighborhood. CJ GUNTHER/EPA, via LandovA resident of Watertown watches as police search an apartment complex. Aram Boghosian for The Boston Globe via Getty While "Suspect No. 1" was killed in an overnight shootout, police are still combing for "Suspect No. 2" who remains at large. Jared Wickerham/Getty Boston Police mobilize in the parking lot of the Watertown Mall. Craig Ruttle/APA police official inspects an object that was picked up by a remote-control device following a shootout with the Boston Marathon suspects early Friday morning. Matt Rourke/AP Police officers aim their weapons. A tense night of police activity that left a university officer dead on campus just days after the Boston Marathon bombings, and amid a hunt for two suspects, caused officers to converge on a neighborhood outside Boston, where residents heard gunfire and explosions. Matt Rourke/AP The surviving suspect has been identified as Dzhokhar Tsarnaev, a 19-year-old from Cambridge, Massachusetts. The other suspect, believed to be Dzhokhar's 26-year-old Russian-born brother Tamerlan, was gunned down in an overnight shootout with police in Watertown. Mario Tama/Getty Police with guns drawn search for a suspect. Matt Rourke/AP A police officer rides on the back of a van at a staging area in Watertown. Zhang Jun/Xinhua, via Landov Officials search an area at Massachusetts Institute of Technology following reports of a shooting, Friday, April 19, 2013, in Boston. State police say a campus police officer at the school died from injuries in a shooting on the campus outside Boston. State police spokesman Dave Procopio says the shooting took place about 10:30 p.m. Thursday outside an MIT building. The injured officer was described as a male but no further information about him was released. The city continues to cope following Monday's explosions near the finish line of the Boston Marathon. FBI/AP This photo released by the FBI early Friday, April 19, 2013, shows what the FBI is calling the suspects together, walking through the crowd in Boston on Monday, April 15, 2013, before the explosions at the Boston Marathon.