Filed at 11:28 a.m. ET
BAM, Iran (AP) -- Iran's president thanked his country's biggest enemy, the United States, for sending help after this weekend's devastating earthquake, as survivors Tuesday mobbed relief trucks and bulldozers dug trench after trench to fill with the white-shrouded bodies of the dead.
International relief workers said they were shifting their focus from searching for survivors in the flattened city of Bam to helping the injured and homes -- and burying the corpses still being pulled from the rubble.
Several hundred relief workers headed home, frustrated over finding so few survivors. The death toll from Friday's 6.6-magnitude quake that shook Bam rose to 28,000, said the coordinator of U.N. relief operations, Ted Peran. At least 12,000 people were injured, the Health Ministry said, and there were fears the death toll could rise to 40,000.
Iranian President Mohammad Khatami vowed to rebuild Bam within two years. The southeastern city -- up to 70 percent of which may have been destroyed -- was home to 80,000 people before the quake.
Khatami also thanked "anybody who has offered assistance, including the Americans." But he downplayed talk that Washington's contribution -- among the largest from nearly 30 nations -- would thaw the two nations' frostly relations.
"Humanitarian issues should not be intertwined with deep and chronic political problems," Khatami told reporters in the provincial capital, Kerman. "If we see change both in tone and behavior of the U.S. administration, then a new situation will develop in our relations."
New aid or pledges continued to arrive. The six Arab states that face Iran across the Persian Gulf committed $400 million to Bam's reconstruction. A team of 80 American relief workers arrived in Bam on Tuesday with medical supplies.
"We have gone out of the rescue phase and entered the humanitarian relief phase of the operation," the U.N.'s Peran said. "There's always hope of pulling more survivors out ... but the window of opportunity is closing rapidly."
Along the ruined streets of Bam, crowds of people jostled for aid handouts. Women in black chadors, some carrying infants, scrambled for old clothes tossed from the back of a truck. Some young men tried to clamber on to the truck to help themselves, but they were pushed back. Others scavenged in the rubble in search of their belongings. One man extracted a pair of trousers and a bottle of water from a pile of rocks where his house used to be.
At Bam's cemetery, where thousands have already been buried, workers dug 130-foot trenches for corpses wrapped in white shrouds. One woman sat alone pounding the ground with her fist.
"I was a good Muslim. I prayed to God all the time," sobbed 44-year-old Alma Sepehr, beside a grave holding the remains of 21 relatives including her daughter, son and husband. "Why did this happen to us?"
At the peak of rescue efforts, 1,700 international relief workers from 30 countries had converged in Bam, Peran said. By Tuesday, the number of rescuers dropped to about 1,500 after seven teams returned home.
"We did not find anyone alive," said Steve Owens of the charity British International Search, waiting Tuesday at the airport in the provincial capital of Kerman for a flight back to England.
"We were a day late getting to the site," Owens said "There should be ways to get teams in quicker. It's frustrating." He said his team spent 14 hours traveling less than 125 miles along a road choked with traffic to reach Bam too late to help.
Russia's Emergency Situations' Ministry said that its 150 rescuers would return to Moscow on Tuesday and a plane carrying humanitarian aid would be sent to Iran on Wednesday.
Monday morning marked the critical mark of 72 hours after the quake, the longest period people are expected to survive in rubble. Occasionally, people survive longer if they are trapped in a pocket of air, but Bam's traditional architecture has limited that possibility. The city's mud-brick houses crumbled into small chunks and powdery dust.
Provincial government spokesman Asadollah Iranmanesh said the United States and Iran's Arab neighbors in the Gulf were among the most generous contributors to the relief effort.
Since the quake, the United States has sent at least eight Air Force C-130 cargo planes to Iran carrying 150,000 pounds of relief supplies, including blankets, medical supplies and water.
The aid comes even though Iran and the United States severed diplomatic ties after the 1979 Islamic Revolution, and President Bush has branded the country as part of an "axis of evil" with Iraq and North Korea.
Secretary of State Colin Powell said in an interview with The Washington Post that Iran's acceptance of U.S. aid is the latest suggestion of a new attitude in Iran that could lead to a restoration of more friendly relations.
Powell also pointed to Iran's agreement to allow inspections of its nuclear facilities and its overtures to moderate Arab governments. "There are things happening, and therefore we should keep open the possibility of dialogue at an appropriate point in the future," Powell said.
Khatami spoke to reporters after holding an emergency Cabinet meeting convened to discuss rebuilding Bam, best known as the site of the world's largest medieval mud fortress, which crumbled in the quake.
"Bam must be put back on the map of Iran," Khatami was quoted as saying by Iranian TV. "We hope that the city will be reconstructed over the next one to two years."
Iran's supreme leader Ayatollah Ali Khamenei pledged $126,000 for rebuilding Bam's shattered homes, Iranian TV reported.
At the cemetery, three men crouched by one grave, crying as they covered a body's face with a piece of cloth.
Elsewhere, Akbar Hesomi, 55, sat on a pile of rubble and watched Iranian rescuers search for four of his relatives with bare hands and shovels in the ruins of what used to be a four-story building.
"My girls, my boys! My girls, my boys," he repeated over and over.
Associated Press reporters Ali Akbar Dareini in Kerman and Alessandra Rizzo in Bam contributed to this report.