A massive forest fire in northern Minnesota might be why some Ontario residents smelled smoke Tuesday afternoon.

A burning smell was reported in some Ontario municipalities, including Burlington, Barrie, Innisfill, Gravenhurst, Bracebridge, Huntsville, Lindsay, Thunder Bay, and Cambridge.

Ontario's Ministry of Natural Resources said the smoke is caused by the on-going forest fire that has been drifting into the province for the last several days.

There are also 61 active forest fires across Ontario, none believed to be strong enough to produce the smoke. More than 30 fires were reported between Sept. 9 and 11 in Ontario, according to the ministry's website.

Curious residents took to Twitter on Tuesday in an attempt to solve the smoky mystery.

The mayor of Innisfill, Ont. tweeted, "Smoke smell in air caused by large forest fires in Minnesota area - smoke should clear out later today-Fire Dept says no cause for concern."

Another tweet, from @BobbysBikeHike, said, "Do you see the orange haze in the sky and smell the burning smoke? It's coming from Minnesota."

And MeaghanDRoy tweeted, "Peterborough smelling like smoke because of wildfires in Minnesota…crazy!"