Pictures obtained by the BBC show large parts of the Canadian city of Fort McMurray in ruins following a devastating wildfire.
The exact scale of the damage is difficult to assess, as access to the city is restricted.
Officials have given few details other than to report that 1,600 homes and other buildings have been destroyed.
However, people who have seen the damage say whole neighbourhoods have been wiped out.
One picture shows the ruins of many houses, with a car untouched by fire. In another, a destroyed church is surrounded by rubble.
Some parts of the city, in the province of Alberta, have been defended resolutely and are still standing.
The city's airport suffered only minor damage despite being licked by flame and engulfed by smoke.
Only the "Herculean" efforts of fire fighters saved the facility, says Scott Long of the Alberta Emergency Management Agency.
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- The images of whole neighbourhoods in ruins are shocking but they will not surprise the people of Fort McMurray who fled knowing that their city was in danger of being consumed by fire.The fire in the province of Alberta covers 850 sq km (328.2 sq miles), and the entire city of almost 90,000 people was evacuated three days ago.Most fled south but some of those who headed north have been airlifted to safety.A police-escorted convoy of 1,500 vehicles was passing through the city along the only safe route to Edmonton and Calgary to the south, but police have told the BBC it has has been suspended because of flames up to 200 feet high on both sides of the road.It will take approximately four days for the Royal Canadian Mounted Police to escort all evacuees from sites north of Fort McMurray, authorities said.For nearby communities though the danger has not receded.Officials are predicting that it will be "weeks and weeks" before the fire is completely out. The region has not had significant rain in two months.
The skies above the empty and smouldering city are full of strange shapes.
There are clouds that billow like bright white cauliflowers, boiling rapidly as they change by the second.
There are clouds illuminated by vertical streaks of a dull red from the fires on the ground.
And there are giant clouds stretching as far as the eye can take in with a single glance, great walls of smoke blown sideways by the strong winds.
The helicopters - almost 150 of them, we are told - look puny in the face of such a dramatic display of nature's power, but occasionally they do seem to be making progress in slowing the fire's march across the plains.
Ultimately though, says Bill Stewart, co-director of the University of California's Center for Fire Research and Outreach, only nature can stop it entirely. Source: BBC News
