A Massachusetts man stabbed six people, two fatally, at a home and a shopping mall south of Boston before he was shot and killed by an off-duty law enforcement officer, authorities said late Tuesday. 

Bristol County District Attorney Thomas M. Quinn III told reporters that Arthur Darosa, 28, of Taunton, crashed a car outside a home in the city, walked inside and stabbed an 80-year-old woman and another woman. The 80-year-old was taken to a hospital, where she later died. The other woman was being treated for life-threatening injuries.

Neighbors told WFXT the women who were attacked in the home were mother and daughter.

“My son was here and heard the loud noise,” a neighbord told the station. “An accident had happened, someone was coming out of the house. [He] realized that person had a knife.”

Darosa then drove to the Silver City Galleria mall, where he crashed a car into the front of a Macy’s store. Quinn said Darosa assaulted multiple people inside the store before running to a Bertucci’s restaurant and stabbing four people, including a 56-year-old man who later died. An off-duty deputy sheriff intervened at the restaurant and shot Darosa dead, Quinn said.

None of the victims’ names were immediately available. 

A motive for the attacks remains under investigation, but state police said they have found no evidence of a connection to terrorism.

“There is no continuing threat to the public,” said Dave Procopio, a Massachusetts State Police spokesman who described the off-duty Plymouth County deputy who shot Darosa as a hero.

The Silver City Galleria was briefly placed on lockdown during the attacks. Store worker Justin Pizzaro told The Boston Globe a mall security guard walked up to him shortly before 7 p.m. local time and told him to close the store gate. 

Taunton, with a population of around 55,000, is located approximately 40 miles south of Boston.

The Associated Press contributed to this report.

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