Last updated 10:48 a.m. EST.
Haitians piled bodies along the devastated streets of their capital Wednesday after a powerful earthquake crushed thousands of structures, from schools and shacks to the National Palace and the U.N. peacekeeping headquarters. Untold numbers were still trapped.
It seemed clear that the death toll from Tuesday afternoon's magnitude-7.0 quake would run into the thousands. The Roman Catholic archbishop of Port-au-Prince was, and the head of the U.N. peacekeeping mission .
International Red Cross spokesman Paul Conneally said a third of Haiti's 9 million peopleand that it would take a day or two for a clear picture of the damage to emerge. The United Nations said the capital's main airport was "fully operational" and open to relief flights.
Aftershocks continued to rattle the capital of 2 million people as women covered in dust clawed out of debris, wailing. Stunned people wandered the streets holding hands. Thousands gathered in public squares to sing hymns.
People pulled bodies from collapsed homes, covering them with sheets by the side of the road. Passers-by lifted the sheets to see if loved ones were underneath. Outside a crumbled building, the bodies of five children and three adults lay in a pile.
The prominent died along with the poor: the body of Archbishop Joseph Serge Miot, 63, was found in the ruins of his office, said the Rev. Pierre Le Beller of the Saint Jacques Missionary Center in Landivisiau, France. He told The Associated Press by telephone that fellow missionaries in Haiti had told him they found Miot's body.
The United States and other nations - from Iceland to Venezuela - said they would start sending in aid workers and rescue teams.
President Barack Obama promising an all out rescue and humanitarian effort to help the people of Haiti overcome the earthquake, which he called a "cruel and incomprehensible" tragedy
The president said the relief effort is gearing up even as the U.S. government is working to account for Americans who were on the island nation when the disaster struck late Tuesday afternoon.
Mr. Obama said he named U.S. Agency for International Development chief Rajiv Shah to coordinate American efforts, and the president called upon all nations to join in helping stricken Haitians. Obama spoke Wednesday in the White House Diplomatic Reception Room.
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The international Red Cross and other aid groups announced plans for major relief operations in the Western Hemisphere's poorest country.
Many will have to help their own staff as well as stricken Haitians. Taiwan said its embassy was destroyed and the ambassador hospitalized. Spain said its embassy was badly damaged.
"Haiti has moved to center of the world's thoughts and the world's compassion," British Prime Minister Gordon Brown said.
Tens of thousands of people lost their homes as buildings that were flimsy and dangerous even under normal conditions collapsed. Nobody offered an estimate of the dead, but the numbers were clearly enormous.
"The hospitals cannot handle all these victims," said Dr. Louis-Gerard Gilles. "Haiti needs to pray. We all need to pray together."
Speaking Wednesday morning to "Early Show" co-anchor Harry Smith, Haiti's U.S. Ambassador said the president of the country and his wife survived the quake.
Raymond Joseph told CBS News that many government employees had survived because they were no longer in their offices when the quake struck just before 5 p.m.
Joseph said the "number one" need for Haiti Wednesday morning was a hospital ship that could dock off the nation's coast and help cope with the many wounded. After that, he said the most urgent needs were search and rescue teams and food and water.
A source told CBS News four U.S. State Department employees sustained serious, but not critical injuries in the quake. The source said there was no damage to the U.S. Embassy. Some U.S. personnel were likely to be evacuated, while additional security personnel were to be flown in.
An American aid worker was trapped for about 10 hours under the rubble of her mission house before she was rescued by her husband, who told CBS' "Early Show" that he drove 100 miles to Port-au-Prince to find her. Frank Thorp said he dug for more than an hour to free his wife, Jillian, and a co-worker, from under about a foot of concrete.
An estimated 40,000-45,000 Americans live in Haiti, and the U.S. Embassy had no confirmed reports of deaths among its citizens. All but one American employed by the embassy have been accounted for, State Department officials said.
Carel Pedrel, a radio show host in Haiti, described to CBS News a scene of darkness and aftershocks in Port-au-Prince.
"I see a lot of people on the streets crying for help. I know there's a lot of people under the buildings collapsed. A lot of traffic, people crying, people bleeding. It's a disaster," Pedrel said.
Even relatively wealthy neighborhoods were devastated.
An AP videographer saw a wrecked hospital where people screamed for help in Petionville, a hillside district that is home to many diplomats and wealthy Haitians as well as the poor.
At a destroyed four-story apartment building, a girl of about 16 stood atop a car, trying to see inside while several men pulled at a foot sticking from rubble. She said her family was inside.
"A school near here collapsed totally," Petionville resident Ken Michel said after surveying the damage. "We don't know if there were any children inside." He said many seemingly sturdy homes nearby were split apart.
The U.N.'s 9,000 peacekeepers in Haiti, many of whom are from Brazil, were distracted from aid efforts by their own tragedy: Many spent the night hunting for survivors in the ruins of their headquarters.
"It would appear that everyone who was in the building, including my friend Hedi Annabi, the United Nations' secretary-general's special envoy, and everyone with him and around him, are dead," French Foreign Minister Bernard Kouchner said on RTL radio.
But U.N. peacekeeping chief Alain Le Roy would not confirm that Annabi was dead, saying he was among more than 100 people missing in its wrecked headquarters. He said only about 10 people had been pulled out, many of them badly injured. Fewer than five bodies had been removed, he said.
Brazil's army said at least four of its peacekeepers were killed and five injured, while Jordan's official news agency said three of its peacekeepers were killed and 33 injured. A state newspaper in China said eight Chinese peacekeepers were known dead and 10 were missing - although officials later said the information was not confirmed.
Much of the National Palace pancaked on itself, but Haiti's ambassador to Mexico, Robert Manuel, said President Rene Preval and his wife survived.
The quake struck at 4:53 p.m., centered 10 miles west of Port-au-Prince at a depth of only 5 miles, the U.S. Geological Survey said. USGS geophysicist Kristin Marano called it the strongest earthquake since 1770 in what is now Haiti.
Most Haitians are desperately poor, and after years of political instability the country has no real construction standards. In November 2008, following the collapse of a school in Petionville, the mayor of Port-au-Prince estimated about 60 percent of buildings were shoddily built and unsafe normally.
The quake was felt in the Dominican Republic, which shares the island of Hispaniola with Haiti, and in eastern Cuba, but no major damage was reported in either place.
With electricity out in many places and phone service erratic, it was nearly impossible for Haitian or foreign officials to get full details of the devastation.
"Everybody is just totally, totally freaked out and shaken," said Henry Bahn, a U.S. Department of Agriculture official in Port-au-Prince. "The sky is just gray with dust."
Edwidge Danticat, an award-winning Haitian-American author was unable to contact relatives in Haiti. She sat with family and friends at her home in Miami, looking for news on the Internet and watching TV news reports.
"You want to go there, but you just have to wait," she said. "Life is already so fragile in Haiti, and to have this on such a massive scale, it's unimaginable how the country will be able to recover from this."