An inmate at the Red Lake jail who severed part of an officer's finger has been sentenced to 6 years, 8 months in federal prison for assault, the U.S. attorney's office reported.

William R. Graves, 40, a member of the Red Lake Band of Chippewa, was sentenced last week by U.S. District Judge David Doty in Minneapolis.

Graves was indicted on June 27 with assault resulting in serious bodily harm. He later pleaded guilty.

According to court records:

On May 31, while in the Red Lake jail, Graves kicked a cell block door closed on

the officer's hand, causing one of the officer's fingers to be severed at the knuckle.

Along with the term, Graves also must undergo a 500-hour drug treatment program and serve three years of supervised release.

Graves had faced a maximum of 10 years in prison.