CHICAGO (AP) -- Chicago-area parents thought their pit bull was to blame when they heard their 18-month-old daughter crying and discovered one of her fingertips had been severed.

Turns out, the culprit was a piranha the family kept in an aquarium.

Doctors determined the bite wasn't from a dog after the girl was rushed to a hospital by ambulance Tuesday night.

Cook County Sheriff's Department spokesman Frank Bilecki tells the Chicago Tribune the girl's father cut open one of two piranhas and found the fingertip. He says doctors tried to reattach the fingertip, but he didn't know if they were successful.

He didn't immediately respond to messages left Saturday by The Associated Press, and a hospital spokesman couldn't provide the information.

Bilecki says the parents were distraught and aren't facing charges.