A homeless man made a grisly discovery along some train tracks in Queens on Saturday afternoon: two plastic bags containing body parts, authorities said.

The bags had been dumped in an overgrown area alongside Long Island Rail Road tracks in Elmhurst.

The parts, which included a skull with hair, a torso and a leg bone, were so badly decomposed that it was not clear whether they came from a man or a woman — or how old the person was.

The Medical Examiner’s Office will perform an autopsy Sunday.