Kenneth Manzanares, 43, was recently sentenced to 30 years in prison for the 2017 crime.
The Alaska Department of Corrections says Manzanares was found unresponsive in his cell Wednesday morning at the Lemon Creek Correctional Center in Juneau.
Correctional officers and medical staff responded. Until emergency responders arrived, they performed life-saving measures.
Manzanares was pronounced dead over 40 minutes after he was found.
He had been in the DOC’s custody for just short of four years.
No foul play is suspected, according to the DOC, and his death is not COVID-19 related.
Manzanares’s death, like every prisoner’s death, will be reviewed by the Alaska State Troopers and the Medical Examiner’s Office.