Former clients of an Oceanside-based dog trainer are accusing him of allegedly injuring and abusing their dogs following the release of disturbing video footage.

As News 12 has reported, video obtained from inside NYDogWorks in Oceanside appears to show a dog being abused by its trainer. In it, a man uses a stick to repeatedly jab a pit bull that is locked inside a crate.

The footage was shared online by Thomas Marrone, of Oceanside, who says his dog was also beaten by the same trainer. He says he released the video in order to warn other dog owner whose pets may still be in the care of NYDogWorks.

SPCA officials say they believe the man in the video is 44-year-old Brian DeMartino. NYDogWorks' website touts DeMartino as an "experienced behavior specialist" who "does not use excessive force."

News 12 went to DeMartino's home in Oceanside Sunday to ask him about the video, but he declined to speak to a reporter.

Milena Apath, a volunteer with animal rescue group Forgotten Friends of Long Island, says they spent thousands of dollars to bring four dogs to DeMartino for training. She says two of those dogs died, and the other two came back more aggressive than ever.

"One of them attacked one of our volunteers unprovoked, and the other was all over the place, snapping, lunging," Apath says.

Anne Kraus, a dog trainer and groomer in Wantagh, says the actions seen in the video are no way to train a dog. "It would accomplish more aggression, not less," she says.

The SPCA is still investigating and no charges have been filed in the case. But DeMartino is scheduled to appear before a judge on Monday on assault charges, stemming from an alleged domestic violence incident.