Boy charged with murdering teacher accused of new assault

BOSTON -- A teenage boy charged with raping and killing his high school math teacher allegedly attacked a female staffer at the juvenile detention center where he is being held, CBS Boston reported Tuesday.

Philip Chism, 15, is accused of assaulting a young woman who works at the Department of Youth Services facility in Boston's Dorchester neighborhood, sources told the station, WBZ-TV.

"The Department of Youth Services is working closely with law enforcement to investigate an assault that took place on a member of the staff at our Dorchester facility. The safety and well-being of our staff is of primary concern and a full review of this incident will be conducted to identify any necessary security enhancements at the facility," said agency spokesman Alec Loftus.

He did not release details of the alleged attack or describe the victim's injuries.

However, WCVB-TV reported that surveillance video showed Chism following the woman into a locker room with a pencil-like object. He allegedly choked and punched her before other staff members pulled him away, the station said.

Chism was 14 when police say he raped, robbed and killed math teacher Colleen Ritzer at Danvers High School in Danvers, north of Boston. Authorities say Ritzer, 24, had asked Chism to stay after school because he was having trouble with his schoolwork. He allegedly followed her into a bathroom and attacked her with a box cutter. Her body was found in a wooded area near the school.

Chism has pleaded not guilty to charges of rape, robbery and murder. No charges were immediately filed in the DYS assault.

Chism was taken to Boston Medical Center for a mental health evaluation, WBZ said.