Image copyright AP Image caption Some of the bodies were still in plastic bags, while others had spilled from ripped sacks on to the ground

Authorities in a suburb of New York are investigating dozens of dead cats found hanging from trees in plastic bags in a small, rubbish-strewn wood.

The cats may have been killed with blows to the head, an animal protection worker in Yonkers said.

Some of the cats had been reduced to skeletons, while others had been killed within the last several days.

The 25-30 cats were discovered on Thursday by a sanitation crew. Some spilled to the ground.

Ernest Lungaro, of the Westchester County Society for the Prevention of Cruelty to Animals, told the Associated Press that investigators had found a baseball bat, two shovels and a metal pipe near the scene.

It is unclear whether the cats were feral or kidnapped pets.