A day after the great Haiti earthquake, the country's president, Rene Preval, speculated that 30-50,000 people may have died -- though officials conceded there was no real way to make an estimate amid the chaos in the poorest country in the Western Hemisphere.
Stunned Haitians piled their dead on the crumbling streets of the capital, Port-au-Prince, and Preval reported stepping over dead bodies.
"Dead bodies are everywhere," said Frederic Dupoux, a resident of the city, in a Twitter feed. "I haven't seen one ambulance or any professional medical care anywhere in Port-au-Prince."
The quake struck late Tuesday afternoon, its epicenter just 10 miles from the densely-populated capital. It had a magnitude of 7.0, making it the worst earthquake to hit Haiti in 240 years.
While specifics on the number of casualties from the earthquake remained unclear, early reports point to heavy and widespread damage.
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Two nurses from Chicago Children's Memorial Hospital happened to be working at a clinic in the town of Gramothe when the earthquake struck. They sent a message early Wednesday morning:
"At least 100 horrifically injured patients were ministered to by this group of 23 as they came to the rescue of two doctors and just a few nurses left to handle the masses of wounded," they wrote.
"Words cannot express our thanks for your prayers tonight. Please continue to pray for Haiti."
"Port-au-Prince is a very mountainous city," said Magalie Boyer, an aid worker for World Vision Haiti, in a telelphone interview with ABC News. "So a lot of people have gathered up their belongings and are carrying them on their heads, carrying them in baskets, carrying them on their backs and just heading up the mountains hoping to find safer ground."
Another aid worker, talking to ABC News on the condition he not be identified, said it was likely that several thousand people had died in the disaster, but that early claims by government officials -- of more than 100,000 dead -- were overblown.
The aid worker said there are not whole sections of Port-au-Prince that have been devastated, though there are pockets. He said some parts of the city have power, some food seems to be available, and traffic is moving, albeit slowly.
This afternoon the United Nations reported that of the 9,000 uniformed peacekeeping personnel it had stationed in Haiti, 16 had died.
Tens of thousands of people are estimated to have lost their homes when poorly-constructed buildings collapsed in the earthquake.
"A school near here collapsed totally," said Ken Michel, a resident of Petionville, a hilly suburb of Port-au-Prince where many diplomats and aid workers live. He surveyed the damage and said, "We don't know if there were any children inside."
Mark Marek, the head of programs for the American Red Cross in Haiti, told ABC News via Skype that much of its rescue equipment would have to be delivered by hand because "the roads are blocked and equipment needs to get into houses that are built on steep inclines and mountains."
Another aid worker e-mailed home, "I myself am an earthquake veteran of the Philippines and Los Angeles, and this was the worst quake I have ever experienced. The Embassy, made of solid stone and steel, bounced and shimmied like an old jalopy driving on a potholed road."