An otherwise healthy dog mysteriously died last night while on a walk with its owner in the northwestern section of Central Park.

An NYPD spokesperson says officers responded to a 911 call about about a dog with head trauma at 110th Street and Central Park West shortly before 11 p.m. The dog died at the scene. Officers searched for ballistics evidence, but did not find any.

WABC reports, "The dog, possibly a black Labrador, was off the leash and had run down a hill. When the man caught up with the dog, it wasn't moving and was later pronounced dead at the scene... The man told police he did not hear gunshots."

The Daily News reports that the dog's owner "ran over to his pooch after it stopped moving and found it dead with a head wound. The owner believed the dog had been shot but cops later said the dog had a deep cut to the head inconsistent with a gunshot wound." According to NBC NY, there was one hole on the top of the dog's head and another under its eye.

The ASPCA will conduct a necropsy on the dog today. Photographer David Torres says the owner was "visibly shaken" and tried to say good-bye to his dog a final time (when the dog was wrapped in plastic), but police led him away.

It's unclear if the dog was deliberately let off leash or bolted from its owner. Dogs are permitted to be off-leash in limited sections of Central Park during certain hours, which include evenings between 9 p.m. and 1 a.m., when the park closes.