At least 12 people were injured after the Jolley Trolley overturned on Saturday afternoon at Dewey Beach, Delaware State Police said.

The trolley, carrying about 22 wedding guests, was being pulled by a van when the trailer started to sway. It then overturned in the southbound lanes of the Coastal Highway, just before 4:45 p.m. Saturday afternoon.

The van stopped immediately and bystanders began assisting, pulling the passengers from the trolley, police said.

Those injured were taken to area hospitals where they were treated for non-life-threatening injuries. The van operator was not injured.

Both southbound and northbound lanes were closed for about two hours, police said. The crash remains under investigation.