MINNESOTA (WCCO) – A federal inmate was sentenced Tuesday to an additional 1.5 years in prison followed by three years of supervised release for assaulting a federal prison guard.

According to court documents, on May 29, Charles Marquis Mitchell, 28, an inmate at the Federal Correctional Institution in Sandstone, consumed a synthetic drug and began behaving erratically.

Mitchell struck a fellow inmate with a closed fist and shoved another into a wall. He did not comply with the prison guards’ orders to lay on the ground and attacked one guard, striking him in the head and face.

After the FBI investigated the incident, the acting U.S. Attorney W. Anders Folk announced the sentencing.

The sentence will be imposed to run consecutively to the sentence Mitchell is currently serving.