The butchered remains of a dolphin washed ashore on a New Jersey beach last week — prompting a federal investigation over the sickening act.

The remains of a common dolphin were found on the beach in Allenhurst, just north of Asbury Park, last Wednesday, the Marine Mammal Stranding Center said on social media.

The aquatic animal “appeared to have been butchered,” the center, which caters to marine animals on New Jersey beaches, noted.

“The animal’s flesh had been completely removed with clean cuts from a sharp instrument, leaving only the head, dorsal fin and flukes,” the center wrote. “The animal’s organs, except for the heart and lungs, had been removed.”

A disturbing photo shared by the center showed the animal’s blood-stained skeletal remains on the beach.

On Tuesday night, witnesses had reported seeing a common dolphin “struggling in the surf one block away” from where the remains were later discovered, the center said.

However, the dolphin was able to swim over the sandbar and back out to sea, the witness reported.

It’s not known if the remains belonged to the same animal, the center said.

The dolphin’s remains were then documented and photographed by the center’s staff, who later buried its carcass on the beach.

The case is being investigated by the National Oceanic and Atmospheric Administration’s Office of Law Enforcement, which declined to comment.

“Anyone who may have information concerning this incident can call the NOAA Fisheries’ Enforcement Hotline at 1-800-853-1964,” the NOAA said.