COLUMBIA, S.C. (WLTX)—The South Carolina Department of Corrections says it regained control of a prison dorm Sunday night after inmates took it over, attacking and hurting three officers. The uprising came nine days after four inmates at another prison were murdered, allegedly by two other inmates.

A criminal justice group has an idea about why the agency is having so many problems. "In our opinion here at Justice 360, and what we've known for a long time, is the Department of Corrections is severely underfunded and severely understaffed,” says Mandy Medlock, executive director of Justice 360, a non-profit group that represents death row inmates and juveniles who’ve been sentenced to life without parole.

Medlock says, “We don't believe it's the fault of Bryan Stirling, who is the head of the Department of Corrections. We don't believe it's the fault of any one staff member or any one warden. It's an overall problem with the system itself in that the state legislature is not properly funding the Department of Corrections. It's understaffed. It's underfunded. They simply cannot afford to hire the staff necessary to properly man, properly guard, the facilities."

In the incident Sunday, inmates at the Kershaw Correctional Institution in Lancaster County took over a dorm around 3 p.m., attacking and injuring three correctional officers. One officer was stabbed, but an agency spokesman says all three were treated for non-life-threatening injuries. The agency sent in an emergency response team and regained control of the dorm by 7:30 p.m. The department has not released any information about what may have triggered the attack.

In the other incident, four inmates at Kirkland Correctional in Columbia were strangled to death in a dorm on April 7th. Two inmates who are serving life for other murders have been charged with killing them. The department has not released a motive in the killings.

Stirling said last year his agency was facing a severe shortage of officers. Lawmakers put enough money in the budget to provide a $1,500 a year raise for correctional officers but there’s still a shortage. He’s scheduled to testify before the state Senate Corrections and Penology Committee Thursday morning about the status of the department.