Updated

A major earthquake hit a distant, sparsely populated region of Russia's Far East early Friday, causing unknown damage and possible casualties, an emergency official said. The U.S. Geological Survey and Japan's Meteorological Agency estimated the quake's magnitude at 7.7.

The quake hit at around 12:30 p.m. local time in the Koryak region, nearly 4,350 miles east of Moscow and some 625 miles north of the largest city in the area Petropavlovsk-Kamchatsky, said Oleg Kotosanov, a duty officer with the regional emergency situations ministry.

Kotosanov told The Associated Press by telephone that there were reports of damage in some villages of the Pacific region, and that emergency officials were flying by helicopter to several locations. Federal emergency officials in Moscow said they had no information about the quake.

Russian news agencies said buildings had been damaged in the coastal village of Tilichiki, including a school, a hospital and an airport. The agencies said there were also some injuries.

Russia's north Pacific coast sits along a major tectonic plate and is frequently hit by earthquakes and volcanic eruptions.

"It's the largest event in this area since 1900," A.B. Wade, a spokeswoman for the USGS, told the AP. "It's a sparsely populated area; up to 2,000 people were exposed to intensive shaking."

By comparison, the great San Francisco earthquake of 1906, which destroyed more than half of the city's buildings and left between 3,000 and 6,000 people dead 100 years ago this week, was estimated at a magnitude of between 7.7 and 7.9.

The Russian quake, centered about 30 miles below the surface, posed no tsunami risk to the western United States and Canada, according to the West Coast and Alaska Tsunami Warning Center.