PONTIAC, Mich. (AP) — A body found in a Pontiac lake by a father and son has been identified as that of a 31-year-old man who went missing in December, officials said.

Police said Friday the body is that of Ryan Patrick Pitts of Pontiac and that his body was positively identified through fingerprints. An autopsy was performed Friday and Pitts’ cause and manner of death were pending.

Pitts’ body was found Thursday in Pontiac’s Harris Lake by a 63-year-old man and his 39-year-old son as they were fishing on the lake.

Relatives reported Pitts missing in January although he had not been seen since December.

Oakland County Sheriff’s detectives issued an alert Monday for help finding Pitts. Crime Stoppers of Michigan had offered a $2,500 reward for tips on Pitts’ whereabouts, the Detroit News reported.