PORT-AU-PRINCE - U.S. troops pulled a man alive from the rubble of a collapsed building in Haiti's destroyed capital on Tuesday, two weeks after a massive earthquake rattled the country.

The 35-year-old man, covered in dust and dressed only in underpants, was carried out from the ruins of a building in downtown Port-au-Prince and was driven off for medical treatment. He did not appear to have any serious injuries.

The rescue, exactly 14 days after the magnitude-7.0 earthquake killed as many as 200,000 people, came as the U.S.-led relief effort was focused on getting help to hundreds of thousands of survivors left homeless, hungry and injured.

Brazilian U.N. peacekeeping troops fired tear gas at a frenzied crowd of thousands of Haitians crowding a food handout outside the wrecked presidential palace as delays in getting help to earthquake survivors persist.

They're not violent, just desperate. They just want to eat, Brazilian Army Colonel Fernando Soares said. The problem is, there is not enough food for everyone.

Facing persistent complaints by survivors that the huge amounts of aid flown in to Haiti is not reaching them on the ground, U.S. and U.N. troops and aid workers have widened and intensified the distribution of food and water.

Some of the food handouts in the capital have turned unruly, although the United Nations said the overall security situation in the city remained stable.

It said about 60 percent to 70 percent of Haiti's police force has returned to work.

At the presidential palace on Tuesday, U.N. troops with shotguns handed out sacks of rice with American flags on them. Armored trucks formed a cordon to control the crowd and people were searched as they entered the checkpoint.

Yesterday they gave us rice, but there was not enough. There were too many people, said Wola Levolise, 47, who is living in the camp with her nine children.

The World Food Program said it handed out 60 tons of food at the camp but ended the distribution early when the crowd got out of control.

The vast majority of distributions in Haiti are being carried out in an orderly manner. There are isolated, regrettable incidents but these are the exceptions and not the rule, a WFP spokesman said.

The U.N. agency said it has delivered nearly 10 million meals to almost 450,000 people since the quake.

Unsanitary living conditions in Port-au-Prince have raised fears of an outbreak of disease.

So far, doctors on the U.S. Navy hospital ship Comfort anchored offshore said they had seen only one case each of typhoid and dysentery, and several of tetanus and malaria.

JOBS PROGRAM

In a bid to get the economy going, the United Nations is offering 150 gourdes ($3.77) a day plus food rations to those willing to take two-week jobs clearing rubble from roads and removing waste that posed a potential health threat to those sleeping on the streets.

More than 5,500 Haitians had already started the jobs, using shovels, hammers, wheelbarrows and trucks to load debris and haul it to landfills, the agency said.

The U.S. military said it could scale back its involvement within three to six months as other international organizations assume larger roles providing security and disaster relief. It does, however, plan to help build a 5,000-bed hospital to provide longer-term care to quake victims.

The United States has dispatched more than 15,000 military personnel to Haiti. About 4,700 are deployed on the ground with the rest on ships off the coast.

There were signs the ruined capital was slowly returning to life. A city garbage truck hauled away piles of rubbish at a makeshift camp near St. Peter's Church and a long line snaked outside a bank in the suburb of Petionville. A street market along Rue Geffrard in Port-au-Prince was crowded and chaotic.

The capital's destroyed downtown commercial area, however, had few open shops. Scavengers picked at smashed buildings for planks of lumber, steel bars and other building materials.

Authorities are trying to relocate at least 400,000 survivors from more than 400 makeshift camps across Port-au-Prince to temporary tent villages outside the city.

FEWER LEAVING THE CAPITAL

Health Minister Alex Larsen said 1 million Haitians had been displaced from their homes in the wrecked capital. The government had tents for 400,000 to be used in the new, temporary settlements, but said it would need 200,000 more.

The need for tents is especially urgent due to the upcoming rainy season, which begins in April.

Almost daily aftershocks have shaken Port-au-Prince since the quake, raising the possibility the city might have to be rebuilt on a safer location, away from geological fault lines.

The United Nations said the exodus of quake victims out of the capital has slowed to a trickle, with less than 1,000 leaving over the past day. Since the quake about 236,000 people have left for the countryside but the United Nations said most had moved in with relatives and large-scale shelter wouldn't be needed.

Donors scheduled an international pledging conference at U.N. headquarters in New York in March.

(Additional reporting by Jackie Frank, Matthew Bigg, Joseph Guyler Delva and Carlos Barria in Haiti, Randall Palmer in Montreal; Writing by Eric Beech; Editing by Kieran Murray and Doina Chiacu)

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