CORVALLIS, Ore. -- A Corvallis teenager was arrested after a surveillance camera captured him preparing to sexually abuse a horse inside a barn, police said.

The owners of the barn installed the camera after reporting an assault on the horse last summer. In February, the owners noticed the halter of their mare had been moved, as well as some food dishes. When they checked the video, they saw a young man sexually assaulting the horse.

Deputy Clay Stephens of the Lane County Sheriff's Office, who watched the video, said the youth, who could not be identified, seemed to be following a "very concise, deliberate, well-thought-out plan."

The owners then installed a silent alarm. On June 7, at around 2:30 a.m., the alarm sounded in the house. The owners looked at the video monitor and saw the suspect preparing to assault the horse. They called the sheriff's office and the 17-year-old was arrested at the barn.

The teenager faces charges of burglary and sexual abuse of an animal.

He was taken to the Linn-Benton Detention Center where he was arraigned and released later the same day. His next court appearance is a hearing June 20.