A crane was being used Wednesday to lift nine rail tank cars back onto the tracks in Sarnia's south end.
City Emergency Management Coordinator Ron Realesmith said CN notified the Sarnia Dispatch Centre of a derailment near St. Andrew Street and Vidal Street around 4 a.m.
"Of the nine cars that were displaced, two of them did have products on board that were a flammable liquid," said Realesmith. "But once again, I just want to reiterate, there was never any concern to the public, and there were no leaks or any hazardous concerns of that nature."
Realesmith said all of the cars remained upright and no injuries were reported.
"The root cause of the derailment is still under investigation and that is something that CN is conducting right now."
He confirmed the train wasn't going very fast.
"I can't give you a specific speed, but it was very slow. They are shunting to another company in town to fill up the cars, so their protocol is very slow, especially when they're going through public property."
Realesmith said cleanup will be ongoing.
"There was some damage to the tracks going across the road, so they will be working alongside the city to resolve that."
Motorists are asked to avoid the area and use Churchill Road to access Scott Road and the eastern part of St. Andrew Street.
-With files from Stephanie Chaves