Fire officials are investigating the cause of a fire aboard a Superior Coach Lines bus around 10:15 p.m. Sunday.

The bus driver had just dropped all his passengers off in Cornwall when he noticed a fire at the back of the bus. He pulled over at the corner of Maypoint Road and the Trans-Canada Highway, tried but failed to extinguish the flames, then called 911.

Charlottetown Fire Inspector Winston Bryan said when his department arrived the bus was engulfed in flames.

"The bus is a fiberglass construction, combustible materials within the seats, a very fast moving fire," said Bryan.

"Some fuel leaked on the site and we're containing that.  Taking all into consideration, there were no injuries at this call. The fire was put out."

RCMP shut down a section of Maypoint Road for several hours last night while firefighters contained the blaze and cleaned up the area.

Officials hope to know more Monday about what caused the fire. Nobody from Superior Coach Lines could be reached for comment.