The B.C. Wildfire Service is asking boaters on Harrison Lake to keep clear of crews working to put out a 20-hectare wildfire in a remote area about 30 kilometres north of Harrison Hot Springs.

Marg Drysdale with the Coastal Fire Centre said the blaze, which is believed to be human-caused, is exhibiting "aggressive fire behaviour."

Drysdale said skimmers, three helicopters, and 43 firefighters are working to get the wildfire under control. 

She said a nearby beach has been cleared for helicopters to land, and boaters are being asked to clear the area of the lake near the fire. 

Drysdale said she couldn't provide any estimate on how long it would take crews to contain the fire.