Ontario's police watchdog is reviewing a police car chase near Hamilton that left in a man suffering life-threatening injuries.

The Special Investigations Unit says the incident occurred early Saturday morning at the New Credit First Nation outside of Hagersville.

The SIU says Ontario Provincial Police officers arrived on the scene of a fight involving several people.

One of the men left in his vehicle and was pursued by police northbound along Highway 6.

The officer then discovered the man's vehicle had flipped over further up the road.

The SIU is automatically called in to review police handling of cases that result in death or serious injuries.

The SIU says it has assigned five investigators, two forensic investigators and a collision reconstructionist to the investigation.

It's asking for anyone with information on the case to come forward.