On Monday rescue workers in larger cities and villages continued to search through rubble hoping to find survivors, but some remote areas have been completely cutoff from rescue efforts.
The U.S. Geological Survey said the earthquake was centered about 60 miles northeast of Islamabad in the mountains of Kashmir, the disputed Himalayan territory divided between India and Pakistan.
An estimated 20,000 people have died in Pakistan and Pakistani Kashmir and officials said they expect that number to rise dramatically as rescue workers sift through thousands of collapsed buildings.
The quake may have killed 2,000 people in India, and many more in remote villages along the India - Pakistan border.
On Monday Pakistani President Gen. Pervez Musharraf sent out an appeal for rescue teams, vehicles, and equipment.
"Our helicopter resources are limited," Musharraf told the BBC Sunday. "We need massive cargo helicopter support."
The United States reportedly sent eight military helicopters from nearby Afghanistan and on Monday Pakistan announced that it would accept an offer of aid from its longtime rival India.
The prime minister of hard hit Pakistani Kashmir called his country a "graveyard"
"It's the biggest natural disaster. It has totally paralyzed Kashmir," Prime Minister Sikander Hayat Khan told Reuters new service. "For the first two days we have been either digging ground to recover bodies or digging to bury them."
Khan said his government is struggling to provide relief after the earthquake destroyed infrastructure and emergency equipment and knocked out communication systems. He said he expects the death toll in Kashmir to rise above 20,000.
The prime minister also said the earthquake's aftermath could be as deadly as the quake itself.
"We are fearing epidemic diseases if the situation remains unchanged," Khan said. "Water is polluted, dead bodies are still under debris, we are trying to control the situation but magnitude of disaster is very great, so we are unable to do it quickly."
Reports from the area said thousands of injured people have yet to receive medical attention and some corpses had been left lying in the open.
Aid groups said some 120,000 people were likely homeless and up to four million could end up being displaced by the disaster.
The United States, Britain, Russia, China, Turkey, Japan and Germany have offered assistance and begun sending aid.
"I spoke to President Musharraf," U.S. President George W. Bush announced Sunday, during a visit from the Pakistani diplomats. "I expressed our nation's deepest condolences. And I told him that we want to help in any way we can. To that end, we've already started to send cash money and other equipment and goods that is going to be needed to help the people in Pakistan."
The U.N. emergency relief coordinator Jan Egeland urged donor countries and agencies to speed relief.
"We know that every hour counts in an earthquake of this magnitude," Egeland said.
Some survivors in the affected areas expressed anger at government officials for what they said was a lack of preparation and an inadequate response.
Major General Shaukat Sultan, a spokesman for President Pervez Musharrf's, defended the government's relief effort.
"There is a lot of damage. There are thousands of houses where relief items have not reached. There are thousands of people who have not been rescued," said Sultan. "But there are thousands of people who have been rescued. There are thousands of people whose lives have been saved."