Officials in Iran say 180 people have been killed in two strong earthquakes just 11 minutes apart in the country's northwest, near the city of Tabriz.

More than 1,300 people are estimated to have been injured in Saturday's mid-afternoon quakes.

State television reported at least six villages in  were completely leveled, while 60 others sustained damage ranging from 50 to 80 percent.

Geological officials differed slightly on magnitude measurements, but both Tehran University and the U.S. Geological Survey put the magnitude of both temblors at 6 or above.

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 they fear 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 tens of thousands of people died.