Cops expecting to find a burglar at a Staten Island home instead discovered an alligator in a bathtub.

An anonymous call came in Tuesday night for a break-in at a residence in Mariners Harbor, according to published reports.

No one was home, but the police did find something surprising, as they put it — a 2- to 3-foot alligator sitting in a bathtub. The reptile has been reportedly turned over to Animal Care and Control.

The alligator may have been an illegal pet, though charges have yet to be filed.