Authorities in the Waco area are investigating a Facebook video showing a group of teenagers mutilating a dead dog for laughs.

The dog apparently died before the video was shot, the Waco Tribune-Herald reports, but it's what the young men did afterward that outraged animal lovers.

"The video is extremely disturbing," Hewitt Police Chief Jim Devlin said Saturday morning, "and even the little bit of information that was with the video prompted us to open an investigation."

The cellphone video shows one of the teens shooting the dog's corpse repeatedly in the head with a handgun, then zooming in on the resulting carnage.

Later the teens place a firecracker in the dog's body and blow it up. The video ends with a closeup of the dog's head on fire.

The Facebook post claims the video was originally uploaded to Snapchat by whomever shot it. The Waco bartender who distributed it said she was doing it to shame those who defiled the dog.

"I'd like to introduce you to a boy from the Waco area ... and show you all what he and his friends think is cool to do to a dogs body," Serena Kristiana Teakell wrote in the post.

The McLennan County Sheriff's Office is investigating the "dog incident," but so far no one has been arrested.

"Any and all charges that apply to this incident will be filed," the department said on its Facebook page, "and we will push for prosecution to the fullest extent."

Anyone with information regarding the case can call the sheriff's office at 254-757-5222.