Emergency officials trying to contain oil slick on North Saskatchewan River

Speaking from atop a fire engine as it raced to the scene, sires wailing, Nikki Booth of Edmonton Fire Rescue Services said nobody had yet been able to determine where the spill was coming from.

"We are currently in the process of putting up booms down the river and trying to capture the substance," she said. "It's coming out of the water outlet (near the Quennell Bridge). That's sort of where all the storm drains would come out as well. If you have a fuel leak somewhere and it's leaking down into a drain, it'll come out through that system."

Booth said a jogger first reported what looked like diesel fuel on the river.

She said emergency officials were working with staff from Epcor, the city's utility, to try and determine what was going on.

"Right now it's half the width of the river," she said. "It is still coming out of the pipe."