UXBRIDGE, Mass. — Police are searching for those responsible for tying up six puppies in a bag and throwing them in a Massachusetts river.

Uxbridge police say a kayaker found the puppies in the Blackstone River on Sunday. An animal control officer responded and took possession of the dogs.

Police say they expect all of the puppies to survive.

Officers are now working to find the person or people responsible for what they call a “heinous act.”