Boston Suspect Manhunt: Controlled Explosion Imminent, Police Say At Presser

At 12:30 p.m. Eastern, major law enforcement officials involved in the manhunt for Boston marathon suspect Dzhokhar Tsarnaev, 19, held a press conference on recent developments.

Governor Deval Patrick, D-Mass., opened the press conference noting it would be brief and those assembled would not take questions. "All [of us] want to thank members of the public who have respected our requests to stay indoors," Patrick said, noting that nobody in the vicinity of the dragnet should open their door unless they can confirm it is a uniformed "identifiable law enforcement officer".

Mayor Tom Menino, D-Boston, assured that he and his colleagues would "keep the public involved" as they receive new information: "We are a city of community [we will] move forward." the mayor said.

Timothy Alben, the superintendent of the Massachusetts State Police said that his officers were making progress in the manhunt, "[we are] going door to door, street to street." he said. He also said that the bomb squad would be executing a controlled detonation of some explosives Friday afternoon in Cambridge, Mass. The detonation will occur on Norfolk Street, and a source interviewed by CBS News' Scott Pelley reported the controlled explosion may be due to explosives that may have been discovered by law enforcement in the process of their search.