A northbound section of Route 1 at Dunstan Corner in Scarborough was shut down for about an hour during Thursday evening’s commute after an accident involving six vehicles.

Officer Travis Hon said three people were taken to Maine Medical Center in Portland with injuries that weren’t life-threatening. Two people got trapped in their cars and had to be extricated.

Hon said in a press release that the cause of the accident remains under investigation but it apparently did not involve speed, drugs or alcohol. Police said the vehicles piled up after one hit a car that had stopped for a traffic light, causing a chain reaction. The accident was reported at 3:37 p.m.

Dunstan Corner is a heavily traveled intersection connecting to the Maine Mall in South Portland, Pine Point Beach in Scarborough and Old Orchard Beach. Route 1, Pine Point Road, Broadturn Road and Payne Road converge at Dunstan Corner.