OTTAWA, June 2 (Xinhua) -- An additional 12,000 people in Canada's western province of Alberta have been placed on evacuation alert as an out-of-control wildfire in the area has been growing, the country's national broadcaster CBC reported Sunday.

The high-level alert was issued due to shifting winds and dry conditions in the area.

As of Saturday, the wildfire covered roughly 280,000 hectares (2,800 square km), almost half the size of the 2016 Fort McMurray wildfire. About 11,000 people were already evacuated.

There are more than 2,300 firefighters on the ground aided by 228 helicopters on Saturday.

The Fort McMurray wildfire broke out in May 2016 in Alberta and brought about the largest wildfire evacuation in the province's history, with upwards of 88,000 people forced from their homes.

Sweeping through Fort McMurray, the wildfire destroyed approximately 2,400 homes and buildings.

With an estimated damage worth 9.9 billion Canadian dollars (about 7.2 billion U.S. dollars), it was the costliest disaster in Canadian history.