Correction officer stabbed 12 times by inmates in Mass. prison attack released from hospital

One of the correction officers who was seriously hurt in last week's prison attack in Lancaster, Massachusetts, is out of the hospital.

The Massachusetts Correction Officers Federated Union said he was stabbed more than 12 times by inmates at Souza-Baranowski Correctional Center. Another officer was stabbed and three others were hurt while responding.

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The Massachusetts Department of Correction is conducting a criminal investigation in coordination with the Worcester County District Attorney’s office, a spokesman said. The inmates identified as being involved with the stabbings have been transferred to other facilities.

Five corrections officers were hospitalized, two of them stabbed, in an incident at the Souza Baranowski maximum security prison, and the officers' union shared that they've been calling for change as well as details from Thursday's incident.

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Surveillance video was released Friday showing the violent attack inside the maximum-security prison. The correction officers union said the video of the assault "shocks the conscience."

"Suffice it to say the Executive Board of MCOFU is stunned, appalled and angry with the level of brutality of this video; but unfortunately, not surprised," the board said in a statement. "We have been warning the DOC of something like this. Our Officers are continuing to get hurt. This horrifying video speaks for itself. Change has to come, and it has to come swiftly."

The union said it is requesting a full security assessment and review of all security related policies, procedures and protocols inside all Massachusetts prisons in order to ensure the safety of every staff member and inmate.

Two state legislators -- Sen. Peter Durant and Rep. Michael Soter -- have also called for an investigation into Wednesday's incident, which is said to have occurred around 6:20 a.m. as two officers were performing routine rounds.