MIDDLESEX TWP - Police are investigating an animal cruelty case in which an unknown motorist let two dogs loose on busy Route 8 Wednesday night.

The dogs were accidentally struck by passing vehicles and killed moments after the motorist drove off.

"This is one of those cases that you simply can't explain," said Middlesex Township police Ed Brooks.

Police have identified just one witness but have asked that anyone who saw what happened to call the station at 724-898-3533.

The witness immediately telephoned police after seeing the dogs struck about 9:30 p.m.

He told police he saw a black, four-door station wagon with the headlights on parked on the side of the southbound lanes on Route 8, just south of the Co-Go's convenience store.

"He saw an occupant in the car pull two dogs out and left them on the road before the (occupant) drove away," Brooks said.

The dogs immediately ran onto the middle of the road and were hit by vehicles.

Because of the darkness, the witness was unable to provide police a description of the person who let the dogs loose. Police don't even know if they're looking for a man or woman.

Brooks said both dogs were wearing collars, but the collars had no identification tags.

The state Department of Transportation sent a crew to pick up and dispose of the dogs' bodies.

"This is definitely a cruelty to animals offense," Brooks said, "but the only way we're going to be able to make an arrest is if someone calls us with more information."