State police said Tuesday that they are investigating the deaths of two people in Old Town whose bodies were found in their locked apartment six days after they were last seen, and are probing whether they are the victims of a drug overdose.

Old Town police discovered the bodies Monday evening when they went to check on the couple at their Water Street apartment when they failed to meet an acquaintance for an appointment earlier that day. The apartment was locked, and police had to get a key from their landlord.

Autopsies done on Mark Savage Jr., 33, and the woman, whose identity has not been confirmed, showed no signs of a crime, said state police spokesman Steve McCausland.

Police believe the woman was Savage’s roommate.

Toxicology tests may help determine if the deaths were drug-related, McCausland said.