BAM, Iran -- Relatives and rescuers used everything from bare hands to bulldozers Saturday to retrieve victims of a powerful earthquake that crumbled vast swaths of this city of mud-brick buildings into powder and frost-chilled rubble, killing thousands of people.
The destruction was so all-encompassing that a reliable death toll in the city of 80,000 was still unavailable. Most people were asleep when the earthquake, which the U.S. Geological Survey measured at magnitude 6.6, struck at 5:28 a.m. Friday.
The Interior Ministry estimated the death toll at 20,000 but officials in the region said it could be double that amount.
"An unbelievable human disaster has occurred," said Akbar Alavi, the governor Kerman, the provincial capital. "As more bodies are pulled out, we fear that the death toll may reach as high as 40,000."
But other officials said later Saturday the number of dead would be lower.
"The figures are not correct; no precise statistics on the number of casualties are available yet but it seems that number of the victims is less," Deputy Governor Mohammad Farshad told the official Islamic Republic News Agency.
The Interior Ministry estimated the number of injured at 30,000.
One American was killed and another injured as they visited the city's 2,000-year-old citadel, a U.S. State Department official said in Washington. The injured American was hospitalized in Tehran, State Department spokesman Lou Fintor said. The victims' names were not released.
Bam, in southeast Iran about 630 miles from Tehran, suffered such extreme damage because most of the buildings are made of unreinforced mud brick and the quake was centered only about 10 miles outside the city, said Harley Benz, a USGS seismologist.
"The communities in this part of Iran are really not resilient to earthquakes," said Benz, head of the National Earthquake Information Center in Golden, Colo. "It's very sad and unfortunate."
Aftershocks registered as high as 5.3, according to the geophysics institute of Tehran University.
Searchers carried the injured in their arms, on stretchers and in the backs of trucks, seeking help outside Bam's ruined hospitals or at the airport while awaiting evacuation to Kerman, the provincial capital about 120 miles away, or other cities.
A provincial government official, Saeed Iranmanesh, said that 3,000 bodies have been recovered and buried, and more than 9,000 of the injured were sent to hospitals throughout the country.
About 150 people, including an infant, were pulled alive from the rubble, Revolutionary Guards officer Masoud Amiri said. The baby was buried more than 24 hours but was listed in stable condition at a hospital, he said.
By late afternoon, a 1 1/2-mile line of vehicles waited to enter Bam as Iranians rushed to find relatives or to bring emergency supplies.
Iran opened its airspace to all planes carrying emergency supplies and waived visa requirements for foreign relief personnel.
"The disaster is far too huge for us to meet all of our needs," President Mohammad Khatami said as he declared three days of mourning.
Governments and relief organizations mobilized around the globe, with rescue workers, search dogs and supplies arriving from a long list of countries.
The United States, which has no diplomatic relations with Iran, will send 150,000 pounds of medical supplies and dispatch teams of about 200 search-and-rescue and medical experts from Fairfax County, Va.; Los Angeles; and Boston, U.S. officials said.
"We greatly welcome any assistance from the United States. We welcome assistance from all countries except Israel," Alavi said.
Israel and Iran are adversaries.
The U.S. airlift could help thaw relations with Iran, which President Bush branded part of an "axis of evil" last year with prewar Iraq and North Korea.