Residents flee as wildfire tears through Canada city

Alberta has declared a state of emergency as crews battle to hold back wildfires.

In Canada's main oil sands city of Fort McMurray, 1,600 homes and other buildings have been destroyed. And more than 80,000 people have been forced to flee.

The wind-whipped flames were being kept from the city's central area thanks to the "Herculean'" efforts of firefighters, said Scott Long of Alberta Emergency Management Agency.

Fort McMurray is surrounded by wilderness in the heart of Canada's oil sands – the third largest reserves of oil in the world behind Saudi Arabia and Venezuela.

Alberta premier Rachel Notley flew to the area to survey the situation, while officials in the evacuation centre had to flee to the south of the city as flames edged closer.