Christian doctors Luke and Nancy Cutherall hoped and prayed the rumours of destruction trickling out of the Pakistani city of Balakot were overstatements. The truth took their breath away.

"We thought descriptions of "devastation' and "there is not one house standing' and "thousands killed' were exaggerations," says Dr Nancy Cutherall.

"We found today, however, that the reports are all too true. Balakot, a town of perhaps 50,000 people has been levelled."

The couple's early morning email to supporters is one of hundreds informing the world of the terrible human face to this tragedy.

The earthquake measuring 7.6 on the Richter scale hit in the mountains of Pakistani Kashmir, near the Indian border, about 95km northeast of Islamabad.

Now piles of rubble lie where cities once stood.

More than 20,000 people are feared dead.

The quake struck early Saturday delivering the worst tremor in a hundred years, followed by 45 aftershocks.

Yesterday morning the Cutheralls and staff based at the Bach Christian Hospital headed for the district hardest hit, normally 90 minutes drive away.

Three miles out from the city of Balakot they had to abandon their vehicle because the roads were blocked with landslides.

They say the scale of the destruction beggars belief.

"Everywhere people are mourning and burying their dead," Nancy Cutherall says.

"Some are still trying to dig underneath the rubble in hopes of finding parents, a wife, or children alive.  Several schools' roofs fell on studying children, killing many.

"Hundreds are walking out, many carrying children or old people across their backs, and some with obvious injuries themselves."

Dr Cutherall says their hospital is preparing for a flood of stricken survivors.

"Balakot's hospital is rubble, as is most of everything in town," she says, ticking off the remaining facilities.

"There is a small hospital near Balakot run by a Christian Pakistani physician. We visited there earlier to find out if we should send medical help. But because of severe damage to their hospital and one residence, the staff is administering first aid under the trees and sending the more serious cases on.

"The main hospitals to the north and south of us are not functional surgically," she says, hinting at the suffering to come.

"Our hospital is the only one for miles which sustained such little damage. God has blessed us with his protection and we desire to help those around us who are suffering."

International aid efforts are swinging into action with Christian agencies offering channels for Australians to donate much needed relief (see fact box for details).

CMS missionaries to Pakistan, Steve and Jenny Sonneman, located in the south of Pakistan were not harmed by the quake.

CMS NSW spokesman David Maegraith says the organisation has a lot to be thankful for.

"CMS has personnel in each of the countries involved though none were in the badly-affected areas and all of them are safe," he says.

A battery of early morning telephone calls have confirmed that workers in Kabul, Afghanistan and Lahore, Pakistan felt the shaking but there was no serious damage.

"The staff and students at Murree Christian School are also all safe," Mr Maegraith says.

Bishop Rafiq Masih from the Diocese of Hyderabad in the South of Pakistan has contacted CMS calling for Christian support.

"It is a national tragedy. This is the worst earthquake in recent times," he says.

"May I humbly request you to please remember us in your prayers."

In the meantime, the Cutheralls and other nearby Christians are struggling to assist on-the-ground relief.

"Luke held a meeting with all the doctors and other senior staff as soon as we returned to plan how to meet the challenge of caring for seriously injured patients who have lost everything," Nancy Cutherall says.

"Missionary doctors from other parts of the country have called and offered their help."

Dr Cutherall says prayer is the most immediate aid most Christians will be able to offer at this time.

"The doctors have been working nearly round the clock. Pray for heath and strength for each of the staff and for opportunities to be salt and light and the love of Jesus to those we meet," she says.

"And pray that the roads will soon be open so that food and tents can be distributed to the needy, and that those who need medical care can be helped."

PHOTO: AAP