FARMINGTON, Maine (AP) — Police have arrested a father nearly 38 years after his infant son's death, which was originally characterized as sudden infant death syndrome.

Maine state police charged 62-year-old Burton "Ben" Hagar with murder Friday.

The Farmington man is accused of killing his 4-month-old son, Nathan, who was found unresponsive in the family's Brunswick apartment and later died at a hospital in May 1979. State police quietly reopened the case in 1991.

This is the first arrest as a result of the work of a cold case unit created last year by the Maine Legislature.

Authorities aren't saying how the infant died. The body was not exhumed.

Hagar will make his first court appearance next week. It's unknown whether he has a lawyer, and a telephone listing couldn't be found.