SHIRLEY, Mass. — A correction officer was assaulted at Souza-Baranowski Correctional Center Tuesday morning, prompting a lockdown of the maximum-security prison.
The lockdown, according to officials, is likely to remain in place until Wednesday morning.
Around 8:15 a.m. on Tuesday, a guard was assaulted in the general population unit of Souza-Baranowski.
An official told Boston 25 News the guard was slashed with a homemade weapon made of razor blades attached to a toothbrush during breakfast time.
The officer immediately called for help.
Three inmates were removed from the unit and the correctional officer was taken to the hospital.
Four responding correction officers were taken to a local hospital as a precaution, in addition to the officer who was assaulted. One suffered a knee injury while another suffered a wrist injury.
The Worcester County District Attorney's Office was notified of the "serious assault," according to prison officials.
Souza-Baranowski remained locked down Tuesday evening, which restricts movement inside and visits.
Officials did not release the identities of anyone involved and did not immediately provide an update on the assaulted officer's condition.
The Massachusetts Correction Officers Federated Union released a statement regarding the incident, saying, in part:
"This union condemns any attacks on our officers and encourages the department to prosecute every incident to the highest extent possible."
This is just the most recent incident involving violence at the correctional center. In January 2017, a fight between two inmates at the prison led to a riot that destroyed a housing unit. During the riot, 47 inmates refused to go back into their cells, using fire extinguishers to destroy computers and camera systems.
The riot went on for three hours before a State Police response team intervened. In total, 15 inmates were indicted on charges including vandalism, malicious destruction and disturbing a correctional facility.
One year ago this week - on Aug. 24 of last year - a fight broke out in a housing unit where six inmates were accused of assaulting six correction officers.
Five of the officers ended up in an emergency room, but none of them sustained any serious injuries.
Souza-Baranowski Correctional Center is also the same prison where former Patriots star Aaron Hernandez committed suicide while on trial for the murder of Odin Lloyd.
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