GENEVA - Up to 200 international United Nations staff in Haiti, including peacekeepers, remain unaccounted for after its headquarters and other buildings collapsed in a devastating earthquake, a spokeswoman said on Thursday.

Between 50 to 100 MINUSTAH (peacekeeping) staff are believed trapped in the building. In total, between 115 and 200 are unaccounted for, but it is an estimate from last night, Elisabeth Byrs, spokeswoman of the U.N. Office for the Coordination of Humanitarian Affairs (OCHA), told Reuters.

The fate of Haitian nationals employed locally by the United Nations was unknown and was also of concern, she said.

On Wednesday, the world body said at least 16 people at its peacekeeping mission, including 11 Brazilian soldiers, had died when its headquarters at the Christopher Hotel collapsed. It predicted the toll would soar.

Haitian President Rene Preval has said that the head of the MINUSTAH peacekeeping mission in Haiti, Hedi Annabi, was killed, but the United Nations has not confirmed that.

MINUSTAH employs nearly 11,000 people -- 9,000 troops and police, but also 490 international civilian staff as well as locals, according to Corinne Momal-Vanian, chief U.N. spokeswoman in Geneva.

In addition, several hundred international staff work for U.N. aid agencies including the U.N. Development Programme, U.N. Children's Fund (UNICEF) and the World Health Organization (WHO).

Tens of thousands of people were feared dead and many were believed still trapped alive in rubble after the 7.0 magnitude quake hit the capital of the Caribbean nation on Tuesday.

TRAGEDY FOR U.N.

This is a tragedy for the United Nations as well as the Haitian people, Byrs told a news briefing. The priority is to save lives, get people out of the rubble and treat the wounded. Every hour counts.
Some 16 search and rescue teams were heading for Haiti, in a huge outpouring from the international community, she said.

The capital's airport is open for humanitarian flights, with only line-of-sight landings as the air control tower was damaged.

The port is not operational as cranes were destroyed, the wharf damaged, and debris lies submerged in the water, posing a potential danger to U.S. cargo ships on their way, Byrs said.

The U.N.'s World Food Programme is checking its warehouses to see whether supplies have been looted or damaged, according to Charles Vincent, director of WFP's office in Geneva.

It hopes on Thursday to distribute rations to 2,400 people in Port-au-Prince, a drop in the bucket, but a start, he said.

Most of the population has not had food for a whole day yesterday. As a result, insecurity is feared and obviously MINUSTAH will be trying to control that situation, he said.

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