CALGARY -- A preliminary report by the province's police watchdog into an incident that injured a Lethbridge police officer Tuesday shows he was hurt when a gun accidentally went off at a shooting range.

The Alberta Serious Incident Response Team (ASIRT) was called to investigate after a police officer was injured Tuesday.

The agency says a number of police officers were at the Lethbridge Police Service's firing range for a training exercise at 10:40 a.m.

During the course, one of the officers was handling a service weapon when it went off, firing a round into a table.

"An officer nearby was struck in the upper (left) leg by what is believed, at this stage of the investigation, to be a fragment from the table, resulting in a serious but not life-threatening injury," ASIRT wrote in a release.

The remaining officers provided first aid to the victim, a 35-year-old male officer, until EMS arrived. The slug from the weapon was later recovered from the wall by investigators.

The officer remains in hospital in stable condition.

ASIRT's investigation is ongoing.