Cops hunt for a suspect on Walnut St. on Friday, Apr. 19, 2013 in Watertown, Mass. (James Keivom/New York Daily News)
A campus police officer at Massachusetts Institute of Technology was shot near Building 32 (Stata) on Friday, Apr. 19, 2013 in Cambridge, Mass. (James Keivom/New York Daily News)
Cops hunt for a suspect on Walnut St. on Friday, Apr. 19, 2013 in Watertown, Mass. (James Keivom/New York Daily News)
Cops detain a man during a hunt for two suspects in the Boston Marathon terror attacks on Friday, Apr. 19, 2013 in Watertown, Mass. One suspect is dead, but another remains at large following violent incidents overnight that took the life of a police officer and shook the outskirts of the city. Authorities confirmed early Friday that the incidents in Cambridge and Watertown, Mass., were directly connected to the Boston Marathon attack Monday. (James Keivom/New York Daily News)
People cheer for the police officers involved in the apprehension of Boston Marathon terror attack suspect Dzohkhar A. Tsarnaev after he was captured at 67 Franklin St. on Friday, Apr. 19, 2013 in Watertown, Mass. Tsarnaev's brother, Tamerlan Tsarnaev, 26, was shot dead in a gun battle with police overnight in the Boston suburb of Watertown. Dzohkhar A. Tsarnaev remains at large following violent incidents overnight that took the life of a police officer and shook the outskirts of the city. Authorities confirmed early Friday that the incidents in Cambridge and Watertown, Mass., were directly connected to the Boston Marathon attack Monday. (James Keivom/New York Daily News)