Ontario Provincial Police say a highway between the northern communities of White River and Hornepayne is closed due to a forest fire causing "extremely dangerous conditions" in the area.
Police have posted photos online showing heavy black smoke alongside Highway 631.
The Ministry of Natural Resources and Forestry says there is currently a wildfire burning 5.5 kilometres west of White River that is not under control.
It says there's another forest fire burning north of Highway 17, in the Kakakiwibik Esker Conservation Reserve, that is not under control.
The province says there is also a new wildfire burning six kilometres east of the town of Chapleau, Ont., that is not under control.
Several communities, including White River, Hornpayne, Chapleau and the city of Elliot Lake, have issued fire bans.