JACKSON, Tenn. (AP) - A man has been sentenced to life in prison for the 2016 killing of a Tennessee Bureau of Investigation agent.

The TBI said on Twitter that Brenden Burns pleaded guilty Monday in the shooting death of Special Agent De'Greaun Frazier. The 35-year-old was killed during an undercover drug investigation in Jackson in August 2016.

Madison County District Attorney Jody S. Pickens said the 24-year-old Burns pleaded guilty to murder in perpetration of attempted especially aggravated robbery, attempted especially aggravated robbery and a weapons possession charge.

Burns accepted a sentence of life in prison without parole.

Frazier was the first agent in the TBI's history to be killed in the line of duty.

TBI broke ground in July on a laboratory and regional headquarters named after Frazier in Jackson.

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