DENVER -- A Weld County man, in trouble previously for owning dangerous dogs, was arrested again after police said one of his dogs attacked a neighbor's dog in Firestone, Colo.

David Riley, 37, was arrested Friday for investigation of second-degree trespassing and unlawful ownership of a dangerous dog, the Longmont Daily Times-Call reported Tuesday.

Police were called to a home on Florence Avenue at 2:40 a.m. on a report of a disturbance involving a dog, the newspaper said. They found a boxer-mix named Scout fighting with a dog in the back yard of the home. They said they also found Riley in the yard.

Police served a warrant at Riley's house that evening, arresting him and confiscating his dog. The dog was taken to the Weld County Humane Society -- the same place another dog with connections to Riley is being held in a separate case. Bruni was being kept after he allegedly attacked a woman earlier this month at Riley's mother's house in rural Weld County.

Bruni was one of three boxers that were seized from David Riley in an earlier case after one bit another woman on her hand on Sept. 3 while she was walking her Siberian huskies in Firestone, Colo., according to investigators.

The three boxer-mixes belonging to David Riley were also blamed for an attack on a worker at the Coal Ridge Animal Hospital in Longmont, where the dogs were impounded while Riley awaited trial in the first case. The 18-year-old worker spent four days in intensive care recovering from several severe wounds sustained in the attack. His injuries required more than 200 stitches to repair.

Riley was sentenced to 60 days in jail for the September attack. After his release on May 1, he was required to keep his dogs in a razor-fenced kennel, or muzzled and leashed when they were outside the kennel.

Upon his release, Riley told the Times-Call that his dogs would no longer bite people because they were trained at a dog academy while he was in jail.

"They've spent a couple months at the Colorado Dog Academy," he told the newspaper earlier this month. "They really trained them good."