A Stillwater prison inmate serving a life sentence for murder was sentenced Wednesday to more than eight years of additional prison time for a rampage in January 2013 that involved six correctional officers and left two with serious injuries.

Derrick D. Brocks, 40, was sentenced by Washington County District Judge Richard Ilkka to 98 months in prison after he pleaded guilty to three charges: first-degree assault causing great bodily harm; second-degree assault causing substantial bodily harm, and fourth-degree assault involving correctional officers.

According to the criminal complaint, Brocks became angered over a scheduling change that affected his recreational time at the prison. As his complaints directed at a correctional officer became more heated, he assaulted her, knocking out several teeth and causing permanent nerve damage.

Other correctional officers rushed to their colleague's aid. Brocks continued his assault, however, causing another officer to suffer a severe knee injury, while three others received minor injuries before they subdued Brocks.

Brocks was convicted of first-degree murder by a Hennepin County jury in 1997 for the August 1996 killing of James Nunn, 25. Nunn was shot seven times while walking with a woman in the 1200 block of SE. 7th Street in southeast Minneapolis. The two men had been at a party in the Dinkytown area before the shooting, and Brocks became angry when a woman he knew left with Nunn, records show.

Jim Anderson • 651-925-5039 Twitter: @StribJAnderson