Manitoba’s police watchdog is investigating after an off-duty Winnipeg police officer rear-ended and detained a driver, who was later found to have a broken rib, last summer.

Around 9:15 p.m. on Aug. 18, a man was driving northbound on Route 90 in west Winnipeg when he was rear-ended by another vehicle driven by a man who identified himself as an off-duty police officer, according to a Thursday news release from the Independent Investigation Unit of Manitoba.

After speaking to a witness at the scene, the off-duty officer told the man he was arresting him for impaired driving, and physically detained him until uniformed officers arrived, the release said.

They arrested the man for impaired driving. He was placed in handcuffs and taken to a police station in the back of a cruiser, and later released on an appearance notice, the watchdog agency said.

When he went to get medical treatment the next day, the man learned he had suffered an acute rib fracture.

He reported the incident to the Law Enforcement Review Agency — the public body to which individuals can file a complaint about police conduct — on March 6.

That agency confirmed the man’s injury via medical reports on March 31 and notified Winnipeg police. 

Winnipeg police, in turn, notified officials with the Independent Investigation Unit, which investigates all serious matters involving police in the province, on Wednesday.

The watchdog said its investigation is still ongoing. 

It’s asking anyone with information or video footage that could help the investigation to contact IIU officials at 1-844-667-6060.