Up to 200,000 people are feared to have been killed in the earthquake that devastated Haiti and three-quarters of the capital, Port-au-Prince, will need to be rebuilt, authorities in the Caribbean country have said.

"We have already collected around 50,000 dead bodies. We anticipate there will be between 100,00 and 200,000 dead in total, although we will never know the exact number," Paul Antoine Bien-Aime, the country's interior minister, told the Reuters news agency on Friday.

If the casualty figures are accurate, the 7.0 magnitude quake that hit Haiti on Tuesday would be one of the 10 deadliest earthquakes ever recorded.

In another development on Friday, the United States was given "senior airfield authority" of Haiti's main airport under an agreement between the US state department and the Haitian government.

Aid flights

Lieutenant General Philip Breedlove, the US air force deputy chief of staff for operations, plans and requirements, said on Friday that the agreement is in effect for the next 72 hours.

The agreement means the US will "schedule and control" flights in and out of the airport, deciding what planes can land and in what order.

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Aid flights have been arriving at the airport faster than ground crews can unload them, prompting aviation authorities to restrict non-military flights for fear jets would run out of fuel while waiting to land.

The United States also plans to send 10,000 US troops to the earthquake-ravaged country to help distribute aid and prevent potential rioting among survivors, the chairman of the US Joint Chiefs of Staff said.

Admiral Mike Mullen said the total US presence in and around the beleaguered country could rise beyond that figure as his military officers determine how much assistance may be needed in the days ahead.

The announcement came as the Pan American Health Organisation (PAHO) reported that the death toll from the earthquake may be as high as 50,000 to 100,000 people,

"A variety of sources are estimating the numbers [at] between 50,000 and 100,000," Jon Andrus of PAHO, the Americas arm of the World Health Organisation, said on Friday.

'Heartbreaking loss'

Barack Obama, the US president, said Tueday's earthquake had inflicted "heartbreaking" losses and pledged Washington would do what it takes to save lives and get the country back on its feet.

"The scale of the devastation is extraordinary ... and the losses are heartbreaking," Obama said at a news conference from the White House.

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Haiti beset by natural disasters
Haitians struggle after earthquake

He also urged Americans to have patience with the relief operation, saying there would be "many difficult days ahead".

Ban Ki-moon, the UN secretary general, said he would travel to Haiti "very soon" to show solidarity with earthquake victims and the staff of the devastated UN mission there.

Aid agencies are struggling to reach the up to three million of people affected by the earthquake which levelled buildings and buried thousands of people in the rubble.

At least 300,000 people were estimated to be homeless in Port-au-Prince, the capital, with one in 10 homes in the capital having collapsed, the UN said.

In a joint news conference at the Pentagon with Mullen, Robert Gates, the US defence secretary, said the primary goal is to distribute aid as quickly as possible "so that people don't, in their desperation, turn to violence".

He suggested that the US is aware of perceptions it could have too-high a profile in the ravaged country.

"I think that if we, particularly given the role that we will have in delivering food and water and medical help to people, my guess is the reaction will be one of relief at seeing Americans providing this kind of help," Gates said.

He said it was vital to get food and water into the country and called the security situation "pretty good," except for some isolated cases of scavenging for food and water.

Gates said the UN peacekeeping force in Haiti has primary responsibility for security in the capital.

Rescue and aid efforts have been been hampered by blocked roads, severed communications lines and the difficulties faced by relief agencies that have lost personnel and seen their office destroyed.

Aid limitations

Governments across the world have poured relief supplies and medical teams into the the country but huge logistical hurdles and the sheer scale of the destruction means aid is still not reaching thousands of victims.

PJ Crowley, a US state department spokesman, acknowledged the limitations of the initial US effort to get water, food and other emergency requirements into Haiti.

He likened the stream of aid thus far as flowing through a garden hose'' that must be widened to a "river".

The arrival off the Haitian coast of the USS Carl Vinson, an aircraft carrier laden with helicopters, essentially provides a "second airport" from which aid can be delivered to the stricken capital, Crowley said.

Mullen said the hospital ship USNS Comfort, with hundreds of medical professionals and medical support, should be off the Haitian coast by the end of next week.

Growing frustration

On the ground, there was growing frustration among the thousands of people living out on the streets of Port-au-Prince who had received little or no help.

US troops arrive at Port-au-Prince international airport [AFP]
Sebastian Walker, Al Jazeera's correspondent in the capital, said: "A lot of people have simply grown tired of waiting for those emergency workers to get to them.

"Thousands of people are streaming out of the city towards the provinces to try to find supplies of food and water, supplies that are running out in the city."

David Wimhurst, spokesman for the Brazilian-commanded UN peacekeeping force, said: "Unfortunately, they're slowly getting more angry and impatient.

"I fear, we are all aware that the situation is getting more tense as the poorest people who need so much, are waiting for deliveries. I think tempers might be frayed."

Shaul Schwarz, a photographer for Time magazine, said he saw at least two roadblocks, formed with the bodies of earthquake victims and rocks, built by Haitians desperate for food and water.

"They are starting to block the roads with bodies. It's getting ugly out there. People are fed up with getting no help," he told the Reuters news agency.

Source: Al Jazeera and agencies