BISHKEK - A strong earthquake struck Central Asia on Sunday but there were no immediate reports of damage or casualties, officials and witnesses said.

The quake jolted an area between Kyrgyzstan, Tajikistan and Uzbekistan, Central Asia's most densely populated corner prone to ethnic tension and instability.

The earthquake was felt throughout the region, mainly in Kyrgyzstan, but there were conflicting reports about the magnitude and epicenter.

The U.S. Geological Survey reported that a 6.3-magnitude tremor struck 35 miles east of Sary-Tash near the borders of Tajikistan and Uzbekistan at 9:52 p.m. (1552 GMT).

The Kyrgyz Emergencies Ministry said a quake measuring about 8 on a 12-point scale of earthquake intensity, hit a remote part of Tajikistan and jolted an area near Kyrgyzstan's second-biggest city, Osh.

"There are no reports of casualties or destruction. We are checking all information," Ramis Satybekov, an Emergencies Ministry official, told Reuters by telephone from Osh.

A Tajik earthquake detection center said the quake struck on the border between Tajikistan, Kyrgyzstan and China.

The governor of Kyrgyzstan's Osh region, speaking to Reuters by telephone, said: "Everyone has been mobilized and we are checking all the sites."

Alla Pyatibratova, a journalist in Osh, said Kyrgyzstan's second-biggest city was calm.

"Everyone felt the earthquake and immediately ran outside. I did not see anything destroyed," she said by telephone. "People returned to their homes after a while."

Earthquakes are frequent occurrences in Central Asia, a region wedged between Afghanistan, Iran, Russia and China.

In 1966, the Uzbek capital Tashkent was flattened by a 7.5 earthquake when hundreds of thousands of people were left homeless. A 6.0 magnitude quake on the 12-level rocked Tashkent this August but there was no damage.