King Tut, a pit bull puppy from Northeast Washington, was killed Friday by someone who stood over the sleeping animal and crushed its skull with a 50-pound slab of concrete, police said.

The 6-month-old dog appears to have been minding its own business that morning, meandering in the vicinity of the Circle Seven Express store in the 1200 block of Mount Olivet Road NE, said Officer Michael Triebwasser of the Washington Humane Society.

He said King Tut, a brindle-and-white male, stopped to rest in the shade behind the store about 9 a.m. and fell asleep on the ground . The assailant, described by witnesses as a man in late 20s, picked up the slab, held it chest high and let it fall on the dog’s head, said Triebwasser, who was still searching for the culprit Tuesday.

“Just horrific cruelty,” he said, adding, “In D.C., acts of animal cruelty, we see everything.” In 18 months on the job, Triebwasser said, he has investigated cases involving dogs that were shot, stabbed and strangled and a raccoon that was intentionally set on fire.

In May, Triebwasser said, he helped secure the conviction of man charged with starving his pet snake to death. The sentence: a suspended jail term, probation and 24 hours of community service.

That case was a misdemeanor. In seeking justice for King Tut and the dog’s owner, whom he declined to identity, Triebwasser said authorities could charge the dog-killer with felony animal cruelty, punishable by up to five years in prison. But they’ll have to catch him first.