The province's police watchdog is investigating after five people were hospitalized following a crash involving an OPP vehicle Thursday night in Belleville, Ont.

Around 11 p.m., an OPP cruiser and a second vehicle collided near the intersection of Dundas Street West and Sidney Street, according to a news release from the Belleville Police Service.

Two officers, an adult who was in their custody, and two people in the civilian vehicle were all taken to the Belleville General Hospital, police said.

Both officers and the 21-year-old driver of the other vehicle suffered serious, but non-life-threatening injuries, the SIU said Friday evening. 

Intersection still closed

On Friday afternoon, the Special Investigations Unit (SIU) confirmed they had invoked their mandate and were looking into the crash.

The SIU investigates incidents involving police and civilians that result in serious injury, death or allegations of sexual assault.

Belleville police said the intersection would likely remain closed for the remainder of Friday, and urged drivers to avoid the area.