A tractor-trailer carrying a load of batteries burst into flames Tuesday evening on the eastbound 401. 

It was just before 11 o'clock when it happened, shutting down all collector lanes of the highway, causing major back-ups since express lanes of the highway were also closed from Allen Road to Yonge Street for work.

O.P.P. say there were concerns about the chemicals from the batteries burning, so residents in the area were told to close their windows and turn off their air conditioning as a precaution.

The driver of the truck escaped without injury, and no word on what caused the fire.