One of two suspects identified in surveillance video at the Boston Marathon has been killed and the other is at large after shootouts with law enforcement officers, according to the New York Times. One officer from the M.I.T. campus police force is also dead, apparently shot multiple times as he sat in his patrol car, and a Boston Transit officer was wounded. Classes at several Boston-area colleges have been canceled as police continue to conduct a house-to-house search in a 20-block area for the remaining suspect. The chase began about 10 p.m. when the pair robbed a 7-Eleven and car-jacked a Mercedes SUV. In the subsequent chase, the suspects lobbed explosive devices at the police in pursuit, the Times reports. For more information, go to www.nytimes.com.