Iran's official news agency (IRNA) says 66 people were killed and nearly one thousand others injured in a series of earthquakes in western Lorestan province.
The report says the towns of Doroud and Boroujerd and scores of villages in between suffered heavy damage. It says rescue operations in the region are continuing.
It adds that Iranian President Mahmoud Ahmadinejad has instructed the interior ministry to mobilize all available resources to the stricken region.
U.S. Secretary of State Condoleezza Rice said (in Blackburn, England today) the United States is prepared to offer humanitarian assistance to Iran's earthquake victims.
The series of tremors began around midnight local time and continued for several hours. The most severe tremor was a magnitude six quake that struck shortly before dawn 0117 Hours UTC - Friday.
Earthquakes are a common occurrence in Iran, which is located on several major seismic fault lines.
In December 2003, a powerful earthquake flattened the ancient city of Bam, killing at least 30-thousand people.