At least 16 UN personnel were killed in an earthquake that struck Haiti's capital of Port au Prince on Tuesday, UN Secretary-general Ban Ki-moon said on Wednesday after an informal meeting of the General Assembly.

The 16 include 11 Brazilian peacekeepers, one Argentinean, three Jordanian police officers, and one Chadian police officer, said Ban.

As this is only a preliminary figure, more casualties are expected, he added.

The UN has said that about 150 of its employees working there are still trapped in collapsed buildings and remain unaccounted for, including the mission chief Hedi Annabi and his deputy special representative Luiz Carlos da Costa.

According to reports from Haitian President Rene Preval, Hedi Annabi is dead. Ban said he has been trying to contact Preval since early Wednesday morning.

"I have only been able to speak with the ambassador here," Leo Merores, who has been trying to arrange for a telephone call. However, no one at UN headquarters appears to have been able to reach Preval because communication lines are either down or overloaded.

"But I am trying to reach him," said Ban.

In the meantime, Ban said he would be dispatching Edmond Mullet, a UN undersecretary general, to assume full command of the UN mission.

Thousands of Haitians are feared dead after a 7.0-magnitude earthquake hit the country on Tuesday. Many are still buried under the rubble of toppled buildings, said Ban, stressing the need for swift rescue operations.

"People buried under the rubble are still alive," he said. "We must save them, as many as possible and we must move immediately."

The UN is expected to issue a flash appeal for aid in the coming days, said Ban. The UN has already released US$10 million from the emergency fund.

There is very serious problem of infrastructure and a lack of heavy equipment to help in search and rescue efforts, said Ban, who added that "the situations seems to be very tough."

Ban said he spoke with US President Barack Obama, who assured him that the United States will deploy all available resources to help in the relief efforts.

Ban praised the commitment and solidarity shown by UN personnel working in Haiti, where he traveled last year with former US President and UN special envoy Bill Clinton.

Ban has said he is not going to Haiti immediately so as not to get in the way of rescue efforts. He said he will decide when to go after Mullet assesses the situation on the ground.

"To the people of Haiti, I say this, 'We are with you.' We are working quickly, as fast as humanly possible," Ban added.

(Xinhua News Agency January 14, 2010)