Haiti has barely begun to assess the devastation caused by the biggest earthquake to rock the area in centuries, but the U.S. ambassador to the poverty-stricken Caribbean nation called it a "disaster of major proportion."
Ambassador Raymond Joseph told "Good Morning America" today that he had no way to estimate how many people may have died in the 7.0 earthquake that hit Tuesday, shortly before 5 p.m.
He pointed to the partial collapse of the presidential palace -- a sturdy, statuesque building constructed in 1918 -- as a marker of how bad the devastation will be among the country's numerous shantytowns and simple homes.
"If a building like the palace, which is very solid, collapsed, then the devastation is going to be worse since the buildings are not up to code in Port-au-Prince," Joseph said. "They are flimsy little abodes."
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The Haitian president Rene Preval and his wife were in the palace at the time of the earthquake, but contacted the U.S. consulate in Florida late Tuesday night to confirm they were unijured.
Joseph said Haiti, especially it's capital, is dotted with small homes that cling to the country's hillsides and were not constructed to stand up to an earthquake of this magnitude. He told "GMA" that he remembered once flying over Port-au-Prince and musing that construction of the city's neighborhoods were a disaster waiting to happen.
"I'm sorry," he said today. "It has happened."
Hospitals are said to have been devastated and overwhelmed by the injured. One clinic director sent out an e-mail plea after the quake: "Port-au-Prince is devastated, lot of deaths. SOS. SOS."
Joseph said Haiti was most in need of a hospital ship stationed in Haitian waters, as well as supplies to help keep residents safe and warm.
Haiti's first lady Elisabeth Debrosse Delatour, he said, "asked for first-time responders and all types of good water, clothes, blankets, anything that would be needed for victims from the outset."
The U.S. promised aid immediately after the quake hit and President Obama has orgnaized a coordinated military reponse. The Navy carrier USNS Carl Vinson is on its way to Haiti and will pick up a helicopter squadron in Florida on the way.
The hospital ship the USNS Comfort has also been activated from Baltimore.
Haiti Earthquake Victim: 'Say a Prayer for Us'
The earthquake was also felt in the adjacent country of the Dominican Republic, where people in Santo Domingo, more than 180 miles away, felt tremors for about 10 seconds.
Witnesses in Haiti report seeing hundreds of victims fleeing into the streets in the seconds after the earthquake began, screaming for help and immediately trying to pull others out of the rubble.
Witness Maggie Boyer, who was in her office building when the shaking started, said she and her fellow co-workers ran out in the courtyard. People immediately began pulling out their cell phones to call loved ones only to find they could not get a line.
"Within the whole vicinity of our building there were many, many walls that had fallen, many, many roofs that collapsed," Boyer told "Good Morning America."
"Say a prayer for us," she said.
Victims were left to wander the streets as rubble piled in the roadways made them impassible to vehicles. Some, she said, simply took out blankets and slept in the median, away from buildings that might have further collapsed on them when the aftershocks hit.
Others, witnesses said, are sitting in the streets, bleeding and waiting for someone to come care for them.
"There are injured people bleeding, sitting on the side of the road, crying, waiting for someone to come take care of them," said Keziah Furth. "A 12 year old boy that I'm taking care of, he's just shaking and trembling. He's freezing to death, he is terrified at the touch of anything."
Quake survivor Joel Trimble said, "I've been here 34 years as a missionary. I've seen hurricanes, I've gone through sicknesses, but I could never, ever imagine something like this."
Describing the sickening sensation of a quake, Trimble said, "It felt like everything is shifting, nothing is sure underneath you."
Getting into Haiti has already proved to be a major obstacle and disease is already a concern.
The country is one of the most impoverished in the western hemipshere.
"You have high rates of TB, HIV, diarrheal disease," Dr. Richard Besser, ABC News' senior health and medical editor, told "Good Morning America."
Though many fear disease caused by dead bodies, Besser said, all resources will be focused in the beginning on caring for those still alive.
"Water is critical," he said. "If you don't get that water, you're doing to die. You'll see people drinking dirty water, which is better than no water at all."