Iranian officials say two strong earthquakes have killed at least 220 people in the northwest part of the country. More than 1,500 people have been injured.

The quakes struck late Saturday afternoon just 11 minutes apart.

State television reported at least six villages near the city of Tabriz were completely leveled, while 60 others sustained serious damage.

The U.S. Geological Survey says a 6.4 magnitude earthquake was followed by a 6.3 quake. Both struck less than 10 kilometers underground.

A series of aftershocks have rumbled through the area, prompting thousands of people to spend the night outdoors. Rescue teams are still searching for victims in collapsed buildings, and officials fear the death toll will rise.

The Red Crescent aid society says it has given emergency shelter to about 16,000 people and is sending in more supplies. Officials say rescuers still have not reached some remote villages hit by the quake.

Earthquakes are common in Iran, but few are significant enough to be noticed. The last major earthquake in Iran was a magnitude 6.6 quake in 2003 in the southeastern city of Bam, where 30,000 of people died.