The mystery behind how a dead dog ended up in a suitcase found floating in a St. Petersburg canal may be solved.

Officers were called to Lotta Boat Rentals on 14th Avenue S at 5 p.m. Wednesday after an employee reported finding the suitcase floating in the canal near a dock.

The employee retrieved the blue hard-shell suitcase and opened it to find a dead female pit bull inside.  The dog was black and gray in color, weighed between 30 and 35 pounds and had suffered obvious trauma to the head and lower body, police said.

Police now say the dog belonged to a mentally disabled couple. They said the dog, named Beloved, got loose during a walk and was hit by a car running across 4th Street.

The distraught couple contacted the Society for the Prevention of Cruelty to Animals. They realized that the dog was dead and were told that it would cost $55 for the SPCA to take custody of the animal.

They attempted to bury the dog on the property of the apartment complex where they lived but the landlord told them they couldn't do that and to place the dead dog in a trash bin.

They refused and decided to submerge the dog in the "lake." They explained this was their dog’s favorite spot.

Police are awaiting the results of the SPCA necropsy to confirm the information.

A name written on the suitcase led police to the address of a St. Petersburg woman, who told the officers she had thrown the suitcase into a community trash bin about six months earlier.

The SPCA took custody of the dog's body and suitcase for further investigation.