At least 25 cats were found beaten to death and strung from tree limbs in Yonkers, N.Y., according to various media reports.

The cats, found Thursday by workers clearing debris from a wooded area overlooking the Hudson River, were killed by blows to the head, Reuters reported.

Many of the cats were found stuffed in plastic bags.

"We pulled on the bag and a little black kitten fell out," Glenn Stefanik of the Yonkers Department of Public Works, told The New York Times. "It was a day or two old."

The cats were found in various states of decomposition, which suggests that they were killed at different times over the past several months, Reuters said, citing the Westchester County Society for the Prevention of Cruelty to Animals (SPCA).

"All of us at the SPCA of Westchester are deeply appalled by this depraved act of animal cruelty," Shannon Laukhuf, the group's executive director, told Reuters.

In a statement on its Facebook page, the SPCA of Westchester said it was working with local police to investigate the case.

"The SPCA of Westchester and Yonkers Police are highly motivated to find those who are responsible for this heinous act. The investigation continues as we follow up leads and conduct interviews," the group said, noting that additional items were removed from the scene for further analysis.

The New York Times described the scene where the cats were found as a tangle of vines littered with beer bottles.

No motive or suspects were apparent as of Friday afternoon, but the case is being treated as a crime.

According to the Times, killing a cat in a "depraved and sadistic manner" is a felony in New York state than can carry a punishment of up to five years in prison and a fine as great as $5,000.

Becky Robinson, the founder and president of Alley Cat Allies, a cat advocacy group, told the Times it her group is offering a $750 reward for information leading to the arrest of the person or people responsible for the crime.

"This is not the work of someone who is a little upset," Robinson said. "This is the work of someone who is deranged."

It was unclear whether dead cats were feral or domesticated. The area where the dead cats were found is near where a colony of feral cats is known to reside, the SPCA told the Times.