By Esme Murphy

MINNEAPOLIS (WCCO) — One of the four Minnesota prison workers injured this week by a convicted murderer in a Stillwater prison is speaking out, saying Minnesota prisons are at times dangerously understaffed.

READ MORE: Towns' 3-Point Play Helps Wolves Edge Knicks 112-110

The attack sent a female corrections officer and a female food service worker to the hospital.

Sgt. Tom Walsh is one of two corrections officers who tackled the inmate and subdued him. Walsh suffered a minor hand injury. Another guard also suffered a minor injury.

“It happened really fast,” Walsh said.

Some 200 inmates were in the dining area at the time of the attack.

“It was an inmate who had a bad day and lashed out, and it was a tragic consequence,” Walsh said.

Derrick Brocks, a convicted murderer serving a life sentence, suddenly attacked a female lieutenant, knocking her to the ground. He then shoved a female food service worker to the floor. Walsh and another officer then punched and jumped Brocks.

“Thank God the staff was there when it happened,” he said.

But that is not always the case, Walsh said. Another video, obtained in 2011, shows guards being attacked at Minnesota prison.

READ MORE: Media Groups Protest Restrictions For Federal Trial Of Ex-Officers Charged In George Floyd's Death

In his 20 years on the job, Walsh says that the population at Stillwater has doubled from 800 to more than 1,600 inmates.

The Department of Corrections says that because of crisis training, the number of assaults in Minnesota prisons has dropped from 47 to in 2010 to 17 in 2012.

But corrections officers say what happened at Stillwater this week is an example of how dangerous their job is.

The American Federation of State, County and Municipal Employees (AFSCME), which represents corrections officers, is asking the department for more guards.

“I just hope we get the staffing we need,” Walsh said.

Citing privacy concerns and an ongoing investigation, Walsh declined to give details of the injuries to the two women, who were treated and released from a local hospital.

Brocks has been transferred to Oak Park Heights, the state’s only maximum security prison.

The Department of Corrections released the following statement Sunday regarding the request for more guards:

“All of Minnesota’s prisons operate with staffing levels that ensure the public is protected and our staff is safe. Staffing levels are just one of many factors that determine how safely a prison can be operated.

MORE NEWS: Sen. Klobuchar Vows 'Consequences' If Putin Attacks Ukraine

“The Minnesota Department of Corrections ensures that order is maintained in its correctional facilities by strictly controlling the movement of offenders and constantly monitoring their activity. Appropriate placement of offenders at the proper custody and security levels also ensures that our facilities are safe and secure. Our staff is highly trained and demonstrates professionalism every day they are on the job. Minnesota incarcerates approximately 9,500 offenders in 10 correctional facilities and the 2,142 uniformed correctional officers we employ are enough to safely supervise these offenders.”

Esme Murphy