BOSTON, March 27 (Reuters) - Investigators continued on Thursday to probe the cause of a nine-alarm fire in a four-story apartment building in Boston's historic Back Bay neighborhood that killed two firefighters a day earlier.
The Suffolk County District Attorney's office said it had assigned an investigator to work with Boston Fire Department officials to determine what had triggered the afternoon fire, as tributes poured in for the slain officers, Lieutenant Edward Walsh, 43, and Firefighter Michael Kennedy, 33.
"These brave men gave their lives in the line of duty, putting the public safety ahead of their own interests," said Boston's Roman Catholic Cardinal, Sean O'Malley, in a statement.
Passersby left flowers outside the firehouse where the two men had been based.
No residents of the building died in the blaze, officials said.
Walsh, a 9-1/2 year veteran of the force, was married and had three children. Kennedy had been in the fire department for 6-1/2 years and was a U.S. Marine Corps veteran, officials said. (Reporting by Scott Malone; Editing by Bernadette Baum)