International aid agencies and governments rushed to send search and rescue teams, doctors and medical supplies to Nepal where an earthquake has killed more than 3,200 people and left tens of thousands without food, water or shelter.
Search and rescue teams from India, Pakistan, the United States, China and Israel were already on the spot to help, said the United Nations, as overwhelmed rescuers dug with their hands through the rubble to look for thousands still missing.
India announced it flew in medical supplies and members of its National Disaster Response Force. China sent a 60-strong emergency team. Pakistan's army said it sent four C-130 aircraft with a 30-bed hospital, search and rescue teams and relief supplies.
Other international search teams have or are scheduled to arrive in the capital Kathmandu, with units from Japan, the United States and Britain equipped with sniffer dogs and equipment for heavy lifting. Australia and New Zealand said they were sending specialist urban search-and-rescue teams to Kathmandu at Nepal's request.
At least 6,000 people have been injured, according to the Nepal government. Treating them and other survivors who are pulled from the wreckage remains a serious challenge.
The 7.9 magnitude earthquake, the strongest since 1934 when a similar intensity quake killed 8,500 people, struck the densely populated Kathmandu Valley Saturday noon local time.
There has been widespread damage and destruction of buildings, roads and other infrastructure, said aid workers, adding that more than 60 aftershocks, including a 6.7 magnitude quake Sunday, had led to further devastation.
As well as financial assistance and relief materials, Nepal has asked the international community for medical teams, supplies and tenting for hospitals, body bags, heavy equipment for removing rubble and helicopters to evacuate the injured.
The U.N. Children's Fund said nearly one million children in Nepal were severely affected by the quake, and warned of water borne and infectious diseases.
It has been difficult to assess the full scale of the disaster as many areas outside of Kathmandu are inaccessible due to damaged roads and landslides. Communications and electricity are intermittent.
Compounding the matter, aid workers say their staff and even those trained in disaster response were themselves traumatised by the disaster and series of aftershocks, with some seeing their family members dying and their property destroyed.
Relief camps are likely to be established in coming days.
An update from the U.N. said transport and logistical problems posed a barrier to reaching remote areas, including the western Gorkha region where the quake triggered landslides.
The U.N. said there is an urgent need for trained doctors, medicine and medical supplies.
Children's rights group Plan International said in a statement it had sent teams to rural areas.
However, there has been little sign of international assistance on the ground so far, with some aid flights prevented from landing by aftershocks that closed Kathmandu's main airport several times Sunday.
After returning to Kathmandu from the country's southeast, Plan's Nepal Director Mattias Bryneson said: “There is widespread destruction, collapsed buildings, severely damaged schools and many blocked roads due to landslides in rural areas.
“It is starting to rain in many areas and all over the region people are living outside with little or no shelter, children are crying and health care facilities are overrun."
Some villages have had to be left to fend for themselves until rescue teams can reach them and with bad weather forecast the priority for many will be food and shelter.