(Corrects spelling to carried from carryied in 8th paragraph)

BOSTON, April 22 (Reuters) - Authorities are investigating whether the Boston Marathon bombing suspect who died after a shootout with police had any connection to an unsolved triple homicide in suburban Boston in 2011, a spokeswoman for prosecutors said on Monday.

The 26-year-old Tamerlan Tsarnaev, identified by the FBI as one of two brothers suspected in last Monday’s blasts, was a close friend of one of three men who were stabbed in the neck in an apartment in Waltham, Massachusetts in September, 2011.

At the time, the Middlesex County District Attorney’s office said it appeared that the victims knew their assailant or assailants and that the attacks were not random.

Tsarnaev’s potential connection to the case surfaced after the website Buzzfeed.com reported that some of his former associates suspect he may have been involved in the murder.

“We are definitely going to pursue any new leads,” said Stephanie Guyotte, a spokeswoman for the Middlesex District Attorney’s office. She said it was fair to say that investigators will check to see if Tsarnaev had anything to do with the crime.

Authorities said the 2011 triple homicide happened at the apartment of Brendan Mess, one of the victims. Tsarnaev and Mess worked out together at a gym and Tsarnaev once introduced Mess to the gym owner as his best friend, according to the Boston Globe newspaper.

Middlesex County in Massachusetts also includes Cambridge, where Tamerlan Tsarnaev and his younger brother Dzhokhar are suspected of killing a Massachusetts Institute of Technology campus policeman on Thursday night before a gun battle with police in Watertown, also part of the county.

It does not include Boston, where investigators believe the brothers carried out last Monday’s bombing at the Boston Marathon finish line, killing three people and injuring more than 170. Dzhokhar Tsarnaev, 19, lay in a Boston hospital under armed guard on Monday following his capture by police in Watertown on Friday night. He was unable to speak because of throat injuries sustained during shoot-outs with police. (Editing by Scott Malone and Grant McCool)