HUMANITARIAN volunteers and emergency service crews from the UK have begun a search and rescue mission in Nepal following the earthquake which killed up to 3,600 people dead and left more than 6,500 injured.

Nine out of 10 Nepalese troops are said to be involved in search and rescue operations, as the country pleads for more foreign aid following the country's worst earthquake disaster in over 80 years.

Most of the 12 Scots on The International Committee of the Red Cross list of the missing in Nepal have been traced. Two Scots remain missing out of around 90 British and Irish people following the earthquake.

One of those originally listed was Darren Alexander Smith, 27, and girlfriend Fiona Lamont, 26, who have contacted family to let them know they are okay.

Another couple Brian Allan and his partner Seobhan McGuigan, from Edinburgh, who were on the list were rescued by British Army Gurkhas after being stranded in Nepal.

Another on the missing dossier, Aberdonian backpacker Mitchell Carpenter, 23, contacted his family from Manang to confirm he and travelling companion Joe McMullen were safe and well.

Heather Chan, 34, who was trekking with friends in the Tsum region contacted her mum Patricia, from Arbroath to let her know she was fine.

Dundee-born Susan McDonald, 41, also reported missing has told her parents, William and Ruth, in Stonehaven, to say she was okay.

Stirling-born Scot Matthew Thorne, 36, who was on Everest basecamp when the earthquake struck used Facebook to reassure relatives.

Family of Ross Smith, 22, from Castle Douglas, Dumfries and Galloway also confirmed he is "safe and well".

Those Scots who remain missing according to the ICRC included John Aitkenhead, 61 who was last in contact several weeks ago before leaving to go trekking in Nepal and Dundee-born Lynda Davis, 50, of Bridge of Earn.

The Foreign Office said it had not received reports of any Britons being killed or injured but embassy staff have assisted 200 people.

At least 17 people were killed on Mount Everest, with many more - including some Britons - stranded.

Among those safe but stranded on the world's highest mountain were Joseph Feeney, from Coatbridge, and Calum Henderson, from Edinburgh, both 21, were on a trekking trip to Nepal as a treat after passing their third year exams.

Communication problems in the worst-affected areas mean families and friends around the world are still anxiously waiting for news of their loved ones.

And international aid to the affected region has been prevented by flights being unable to land and huge traffic jams on the roads out of Kathmandu

Aid workers reported "huge logistical difficulties" as road closures and communication problems have thwarted some efforts.

The Disasters Emergency Committee (DEC) in Scotland is to announce its appeal to help survivors of the devastating Nepal earthquake which has been boosted by a £250,000 donation from the Scottish Government.

Leigh Daynes, UK director of medical charity Doctors of the World, said: "Nepal's health system was vulnerable before the earthquake, especially in rural areas.

"Now hospitals are utterly incapacitated, infrastructure has been decimated and thousands of people are sleeping on the streets. With monsoon season only weeks away, this is a catastrophe of the highest order and demands an urgent medical response.

An RAF plane packed with supplies has been dispatched to the crisis zone, while charity workers, experts and firefighters from across the UK have already begun the search for survivors.

The 7.8-magnitude quake struck just before midday on Saturday, sending tremors through the Kathmandu Valley and the nearby city of Pokhara.

Mike Adamson, chief executive of the British Red Cross, said: "As the death toll continues to rise, it is our absolute priority to continue the search and rescue operations and get aid to those left stranded.

"The Red Cross has been working in the Kathmandu valley for the last three years, informing communities of what to do in the event of an earthquake. But though many of the newer buildings have survived, the older infrastructure was not able to withstand the force of the earthquake."

Some 67 firefighters from the International Search and Rescue Team (UKISAR) are among those helping.

The team will be able to provide specialised, technical search and rescue assistance in collapsed structures. This will include locating and rescuing people, canine support, medical teams, engineering, assessing the damage and stabilising scenes.

To donate to the SCIAF Nepal Earthquake Appeal, log onto www.sciaf.org.uk or call 0141 354 5555