Bodies littered the streets of Haiti's devastated capital on Wednesday after a powerful earthquake that may have killed thousands from shanty towns to luxury hotels and even the presidential palace.

With victims pinned under debris and powerful aftershocks rattling the country, looting broke out soon after the 7.0 magnitude quake which spared no part of the capital Port-au-Prince, which was close to the epicentre.

Injured residents of the crowded city poured into the streets screaming in panic with each new tremor. Many bodies were just left in the streets or crushed under debris.

The quake toppled the cupola on the gleaming white presidential palace, a major hotel where 200 tourists were missing and the headquarters of the UN mission in Haiti where up to 250 personnel were unaccounted for.

The head of the force was among those missing.

Jordan reported that three of its peacekeepers were killed and 21 wounded in the quake, the most powerful to hit the country in more than a century.

Eight Chinese peacekeepers were buried in rubble and 10 were missing, China's state media said.

Estimates of the death toll ranged from hundreds to thousands but with every hour passing it was becoming clear that the destruction and loss of life was catastrophic.

A major international relief operation was set under way with the United States, France, Britain and other countries promising help.

Two hundred foreigners were missing at the Hotel Montana, French Secretary of State for Cooperation Alain Joyandet said.

"We know there were 300 people inside the hotel when it collapsed, only around 100 have got out, which greatly concerns us," Joyandet told French radio. Related article: Scenes of horror

A hospital in the suburb of Petionville collapsed, as did ministries, schools, homes in luxury districts and hillside shanties, businesses and markets.

Police, UN and Red Cross vehicles tried to ferry the wounded to hospital, but progress was slow as roads were torn up by the powerful ripples from the quake.

The US Geological Survey (USGS) reported 27 strong aftershocks hit the country in the hours after the initial 2153 GMT quake.

USGS geophysicist Susan Potter said the last earthquake of such magnitude to strike Haiti was in 1897, and possibly as far back as 1770.

Sara Fajardo of Catholic Relief Services told AFP that buildings across the street from their headquarters collapsed, and that staff were terrified the aftershocks would topple more buildings.

"Most of the Catholic Relief Services staff is going to be sleeping on the CRS office compound but they're sleeping outside because they're too afraid to sleep indoors out of safety concerns," Fajardo said.

"The center of Port-au-Prince has been destroyed, it's a catastrophe," wailed a man named Pierre, so traumatized he could hardly speak as he surveyed the disaster.

Haiti's ambassador to the United States, Raymond Alcide Joseph, described the quake to CNN as "a catastrophe of major proportions."

Haiti's ambassador to Mexico, Robert Manuel, told reporters that Haitian President Rene Preval and his wife "are alive and well" but did not provide further information on them.

The headquarters of the UN mission in Haiti (MINUSTAH), which has served as a peacekeeping mission since 2004, was destroyed. "There are numerous people underneath the rubble, both dead and injured," a local employee said. Related article:World gears up to help Haiti

UN chief Ban Ki-moon was to meet top advisors on Wednesday to decide how to respond to the emergency.

Nations around the world offered aid and the United States, France, Canada and governments across Latin America geared to send help, while the international Red Cross mobilised relief supplies from Panama.

The California Nurses Association, the largest registered nurses union in the U.S., has also issued an urgent call for nurses to volunteer to assist the injured in Haiti. Details are still being worked out, but nurses can sign up to join the relief effort online.

The New York Times has compiled a Twitter list of users of the social network who are in Haiti or providing useful information on the aftermath of the earthquake there.

US President Barack Obama said "My thoughts and prayers go out to those who have been affected by this earthquake."

Pope Benedict XVI urged a generous response to the catastrophe. The pope lamented Haiti's "tragic situation (involving) huge loss of human life, a great number of homeless and missing and considerable material damage."

Former Haitian president Jean Bertrand Aristide, exiled in South Africa since his 2004 ouster called it a "tragedy that defies expression." Related article: Exiled leader mourns quake victims

Aid group World Vision said it would begin distributing first aid kits, blankets and potable water to survivors on Wednesday.

This "is especially devastating in Haiti, where people are acutely vulnerable because of poor infrastructure and extreme poverty," Edward Brown, World Vision's US relief director, said in a statement.

Already the poorest nation in the Americas, Haiti has been hit by a series of recent disasters.

Three hurricanes and a tropical storm pounded Haiti in 2008, killing 793 people and leaving more than 300 others missing, according to government figures. Chronology:Major quakes and tsunamis

The country was also gripped by a political stand-off in 2008 amid riots over sky-rocketing food prices. UN troops are a regular sight in the country.

Seventy percent of Haiti's population lives on less than two dollars per day, and half of its 8.5 million people are unemployed.

Haitian radio DJ Carel Pedre gives an eyewitness account of what happened when the recent earthquake struck the nations' capital via YouTube:

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A Reuters video via a CBS News channel on YouTube, starts with images of the collapsed presidential palace in Port-au-Prince:

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With AFP