Rescue workers and relief goods started pouring into Haiti from around the world Thursday but aid groups were running into huge challenges trying to reach quake survivors trapped in the rubble or wandering homeless and hungry in the streets.
Ship deliveries were impossible to Port-au-Prince because the Haitian capital's port was closed by damage. It airport was opened but strained to handle a flurry of incoming flights carrying experts and aid.
Fearful of going near scores of quake-damaged buildings, Haitians stood or rested in the roads, slowing the transport of food and other crucial aid.
"It's chaos," U.N. humanitarian spokeswoman Elisabeth Byrs told The Associated Press. "It's a logistical nightmare."
Severe damage to at least eight Port-au-Prince hospitals made it nearly impossible to treat the thousands of injured or prevent outbreaks of disease, said Paul Garwood, spokesman for the World Health Organization.
Even as the United Nations stepped up its massive aid operation, the world body was trying to determine how many of its own staff were killed in the magnitude-7 quake that struck Tuesday.
"It's very difficult to give an exact number," said Byrs. "This is also a tragedy for the United Nations."
She said up to 100 U.N. staff were trapped in the main U.N. peacekeepers' building, which was destroyed.
Byrs said 40 search-and-rescue teams from around the world had started arriving in Haiti to look for survivors trapped inside collapsed buildings. But to find and save people, the rescuers will need heavy equipment to lift tons of rubble. Some teams have that equipment — including ones from Britain and Iceland — but many don't.
Although impoverished Haiti has virtually none of those machines, the neighboring Dominican Republic does and can help meet the need, said Charles Vincent of the World Food Program.
"We'll have to see how that works out over the coming days," said Vincent. "The U.S. military will also be bringing in some equipment."
He said the lack of working phones and other communication facilities "is still the greatest handicap for everybody" involved in the relief efforts.
Vincent said all WFP staff were exhausted because they have been working around-the-clock to care for Haitians who had sought shelter in the agency's parking lot in Port-au-Prince.
"Most of the population has not had food for the whole day yesterday and today," he said.
The U.N. food agency hoped to able to feed people for the next two weeks from warehouses set up to handle previous disasters in Haiti such as hurricanes — as long as the warehouses aren't looted or damaged, he said.
The desperation situation has aid groups fearing a surge in lawlessness, he said.
U.N. peacekeepers will be patrolling to try to control looting but they are dealing with many deaths and injuries of their own, he added.
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