A K-9 with the Waco (TX) Police Department reportedly turned and attacked his handler while the team were serving an arrest warrant on Friday, according to the Star-Telegram.
Officers were with U.S. Marshals serving an arrest warrant at a North Waco home at the time of the incident.
When the dog attacked his handler, another officer was forced to open fire on the animal, killing it.
Police have not yet named the officers or K-9 involved.
"Please say an extra prayer for and keep our K-9 teams and other officers involved in yesterday's incident in your thoughts this weekend," Waco Police said in a Facebook post.