The teen accused of sexually assaulting and murdering his math teacher allegedly attacked a woman working at the state facility in which he was being held.
In a statement, the Department of Youth Services said it is working with police to investigate the attack on a worker.
"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 Alec Loftus, a DYS spokesman.
A spokesman for the Suffolk County district attorney's office said the incident happened Monday at a Dorchester DYS facility. The worker, a woman in her late 20s, did not suffer serious physical injuries. State police assigned to the office are conducting a "very active investigation," said Jake Wark, the spokesman.
No charges have yet been filed and both agencies declined to identify the attacker or reveal details of the attack.
However, The Salem News reported that Philip Chism, now 15, was responsible for the attack on the female worker and that he is under guard at Boston Medical Center.
Chism was 14 when he allegedly raped and killed his 24-year-old Danvers High School math teacher Colleen Ritzer last year. He has pleaded not guilty.
Follow Michael Naughton on Twitter @metrobosmike.