An inmate at the Maine State Prison died Sunday afternoon, according to a news release issued by the Maine Department of Corrections.

Deputy Commissioner Jody Breton said 63-year-old Willard Eastman died around 2:45 p.m. at the maximum security prison in Warren. Eastman had served about 21 years of a 50-year sentence for murder, Breton said.

Maine State Police are investigating Eastman’s death, and the state Medical Examiner’s Office has been notified.

According to a report in the Kennebec Journal, Eastman and his friend, Dana Craney, were arrested in May 1993 in the slaying of furniture auctioneer Leon Michaud, whose body had been discovered by two woodsmen in a culvert of a rural road in Auburn in December 1990. Michaud had been shot six times.

Craney told police that he had killed Michaud and robbed him of about $2,000 because his rent was due and he had no Christmas presents for his children, according to court records.

Eastman and Craney were convicted of murder and robbery in 1994. Their appeals to the Maine Supreme Judicial Court were rejected in 1995, and an appeal to federal court was denied in 2009.