Following a major earthquake in Nepal and subsequent deadly avalanche on Mount Everest, a Foreign Office spokesperson told ITV News:
The Kathmandu earthquake has a decent chance of claiming tens or even hundreds of thousands of lives, according to alarming projections from the US Geological Survey.
The numbers in the graph below are only projections, but it is clear that more bad news is probably on the way.
Another projection suggests that the economic impact of the quake is likely to reach $10bn (£6.6bn) or more.
As hospital staff struggle to cope with the influx of injuries, members of the public help out in makeshift medical stations on the streets of Kathmandu.
It comes as a senior home ministry official told Reuters that the death toll had risen again to 688.
At least 618 people have been killed in a deadly earthquake in Nepal, a government official has told Indian television.
Eight people are said to have died after an avalanche buried part of the Base Camp at the foot of Mount Everest today.
"The toll could go up, it may include foreigners as well as sherpas," Nepalese tourism official Gyanendra Shrestha said.
It is believed that the avalanche was caused by the devastating 7.9-magnitude earthquake which struck Nepal this morning.
Earlier, a Romanian climber tweeted about a 'huge avalanche' and said he was forced to run for his life.
- Officials say at least 449 people have died following a 7.9-magnitude earthquake
- The quake has reportedly triggered avalanches in the Mount Everest
- Pictures show widespread devastation across Nepal
As the dust settles from this morning's massive quake, dazed Nepalese have begun searching the wreckage of their former homes and offices in the search for survivors.
The death toll from the Nepal earthquake has risen to 449, Nepalese officials say.
Police deputy inspector general Kamal Singh Bam is quoted by Reuters as saying: "The number of dead so far is 449."