In the Iranian city of Bam, cemeteries are overflowing with fully-clothed corpses. Hundreds of bodies have been tipped into trenches hollowed out by mechanical diggers. Many died in their sleep: Friday's earthquake, measuring 6.3 on the Richter scale, struck before dawn. The United Nations co-ordinator in Bam says there is consensus that the rescue phase is ending, meaning there is almost no hope of finding survivors. Iran's Interior Minister said this morning: "We've already buried 15 thousand people and it's my impression, with the scale of the disaster, that the death toll will exceed 20 thousand." The earthquake flattened about 70 percent of the buildings in this ancient city. Many of the structures were made of mudbrick so when they collapsed they left no protected spaces or airpockets. Rescue workers from 21 countries have been working alongside Iranians. A Finnish rescue team said only 30 people were dug out alive overnight. Sniffer dogs and hi-tech ultrasound equipment have helped locate hundreds of people but with extremely low temperatures time is running out. There are reports of young men armed with pistols and assault rifles stealing tents provided by the Red Crescent. The UN team arrived on Sunday morning to find many residents sleeping outside as many buildings risked collapsing. Experts have warned of aftershocks as strong as the earthquake. Iran says it welcomes help from everywhere except Israel. A U.S. Air force plane has brought in a first shipment of medical and humanitarian supplies. **PHOTO CAPTION*** A truck is totally destroyed and covered by rubble in the heart of the ancient city of Bam, December 28, 2003. (REUTERS/Wolfgang Rattay)