An explosion caused by a gasoline truck crashing into a bus in southeast Iran late last night killed more than 70 people and injured another 100.
"The disaster is so grave we cannot identify faces and cannot differentiate between corpses," the governor of the southeastern city of Zahedan, told state television.
He said the accident happened when the bus was unable to stop at a police checkpoint at Nosratabad.
Five other buses were then hit by the fireball. Television showed bodies charred beyond recognition.
Nosratabad lies on the road from Zahedan to Bam, which was hit by an earthquake last year that killed more than 20,000 people. The road is dotted with checkpoints because it is the main route for drugs smugglers taking opiates from Afghanistan and Pakistan to the West.