Colorado flooding rescue operation continues
The US state of Colorado is continuing a large-scale rescue operation after severe flooding left five dead and hundreds unaccounted for.
Thousands of people have been forced to evacuate from affected communities.
The National Guard has been deployed to one town to supply food and water while inhabitants await rescue.
Although flood waters are now subsiding, more rain has been forecast and authorities have warned of more possible flash flooding.
A spokesman for Boulder County said that 200 people were still unaccounted for, but said that some of them may simply be out of contact with family and friends, or awaiting rescue.
However, the sheriff of Boulder County, Joe Pelle, said officials are "assuming that there may be further loss of life or injuries".
"I hope and pray that's not the case but, given the devastation in some of those closed canyons, it's certainly a high probability," Mr Pelle said.
Mr Pelle said that emergency services had not been to respond to residents in some areas because the damage to the road network had been so bad.
While National Guard helicopters and truck convoys have managed to reach stranded canyon communities where thousands of stranded residents are eager to escape the Rocky Mountain foothills, not everybody was willing to go.
Dozens of people in the isolated community of Jamestown wanted to stay and watch over their homes despite being warned against doing so by the authorities.
Rescuers are using helicopters to airlift those still stranded in the mountain village of Jamestown, the BBC's Alastair Leithead reports from Los Angeles.
The National Guard has been using large trucks to get through the floodwaters in the town of Lyons to deliver food and water to those stills trapped by the floodwaters.
Towns such as Jamestown, Lyons and Longmont have been reduced to islands by the swirling waters.
Days of heavy rain have caused severe damage to property and forced the rescue of more than 2,500 people, Boulder County authorities have said.
More than 15in (38cm) of rain - nearly half the region's annual average - fell in a single week, according to the National Weather Service.
President Barack Obama has signed an emergency order approving federal disaster aid for Boulder County.
On Saturday, Colorado's Office of Emergency Management issued further evacuation orders on its Twitter feed for several rural communities.
Wall of water
The torrent began on Wednesday, and has been dubbed a "100-year flood" by officials.
Colorado Governor John Hickenlooper told local radio earlier this week that there had been "a staggering amount" of rainfall.
"Given the drought situation we've had, it was almost a year's worth of rain," he said on the KBCO radio station.
Part of US Highway 36 was closed after it was washed out, and several other stretches of road in the state have had to be shut.
A 20ft (6m) wall of water was reported in Left Hand Canyon, north of Boulder on Thursday, according to National Weather Service meteorologist Bob Kleyla.
The prolonged rain has been blamed on a low-pressure weather system hovering over Nevada which is drawing moist air out of Mexico into the Rockies' foothills.
With hillsides stripped by recent wildfires, the water was funnelled through narrow canyons, worsening the impact of the floods.