At least another 30,000 people have been injured in the disaster, which hit the city of Bam on Friday.

One regional official said: "If we consider that, on average, five people lived in each house, we can say that the death toll will reach 50,000."

Charity workers are looking after at least 100,000 survivors who have been left homeless after the quake.

Search scaled down

They are providing shelter, food and heat for the survivors who are facing cold nights in the open air.

But the search for more survivors has been scaled down now, with the focus now shifting to helping the city recover from the tragedy.

Iran has promised to rebuild the city, which was a major tourist attraction for the country.