The earth shake, of a density of 6.3 on the Richter scale devastated the city of Bam, including the historic citadel. "The historic quarter of the city has been completely destroyed and caused great human loss", said Mehran Nourbakhsh, chief spokesman for Iran's Red Crescent.

According to the report most of the buildings inside the Bam complex have been completely destroyed", the official news agency IRNA reported from the area.

Preliminary estimates offered by local authorities on Friday night put the death toll at around 6.000, but other sources said there was still no precise number of dead and wounded.

"The quake hit the city when most of the people were in bed, raising fears that the death toll may go higher", Kerman’s Governor Mohammad Ali Karimi told reporters after surveying the city of 80,000 people from helicopter.

"About 60 percent of the houses, made mostly of earth and mud, are destroyed", he said, adding that water, power and phone lines were cut.

"The situation in Bam is worrying. The scale of the damage and deaths is widespread and the number of victims is high", Mr. Karimi said on the State-controlled Television.

Relief teams set up their headquarters in a public square in Bam because their offices in the governor's building had been ruined, Karimi told state radio.

Calling on the people not to come to the devastated city in search of relatives and to stay home until phone service was restored to try to find relatives, Mr. Karimi said worried relatives from surrounding areas were heading to Bam and causing massive traffic jams that were slowing rescue efforts.

"We are doing everything we can to rescue the injured and unearth the dead", he added.

About 500 people have been evacuated to hospitals in Kerman, where they are in critical condition, Iranian state television reported, quoting local authorities.

The United Nations disaster management team in Tehran has asked the Iranian government if it needs help and was to meet later Friday to assess the situation, said Elizabeth Byrs, Geneva spokeswoman for the U.N. Office for the Coordination of Humanitarian Affairs.

The United States that has no diplomatic relations with the Islamic Republic said it was offering humanitarian assistance. "This is a terrible tragedy", said a spokesman for the White House.

Italy, as current president of the European Union, was coordinating EU aid to avoid duplication and U.N. officials said they were releasing an immediate emergency grant of $90,000 to help Iran handle the aftermath of the quake and had sent experts to help assess the damage.