ANKARA, Turkey (AP) -- Turkey's state-run agency says a powerful earthquake has collapsed some buildings in the center of eastern city of Van.

The Anatolia news agency says rescue workers are trying to reach people believed to be trapped under the wreckage of a seven-story building in Van, close to the Iranian border.

The earthquake with a preliminary magnitude of 7.3 struck eastern Turkey on Sunday, the U.S. Geological Survey said.

Turkey's Kandilli observatory gave it a preliminary magnitude of 6.6.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

ANKARA, Turkey (AP) - The U.S. Geological Survey says its preliminary measurements say an earthquake that has struck eastern Turkey has a magnitude of 7.3.

Turkey's Kandilli observatory earlier gave it a preliminary magnitude of 6.6. There are no immediate reports of damage or injuries.

Both agencies say the quake occurred at 1:41 p.m. (1041 GMT) Sunday. Its epicenter was in the village of Tabanli in eastern Van province, bordering Iran.

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