Boston police say they shot and killed a knife-wielding man who attacked officers and emergency medical personnel.

Police say they were called to the South End neighborhood early Sunday by medical personnel who had tried to calm the man and were then attacked.

The man hasn't been identified.

Boston Police Commissioner William Evans says the man swung the knife repeatedly at police officers. He says the officers unfortunately had no choice and they fired.

WBZ-TV reports that two medical personnel suffered head and back injuries and the officers involved were also taken to the hospital.

The station says the mother of the 31-year-old man had reported that he was having a paranoid schizophrenic episode.

The Suffolk County District Attorney's office is investigating, as is common procedure with fatal police shootings.