Taipei: A 6.5 magnitude earthquake struck off the southeast coast of Taiwan on Monday, the US Geological Survey said.

The quake swayed buildings in the capital, but there were no immediate reports of casualties or damage and no tsunami alert was issued.

The quake hit at 10:59 a.m. local time (0259 GMT), 195 miles (295 kilometres) off the southern Taiwan city of Taitung at a depth of 6.2 miles (10 kilometres), the USGS said. The agency's initial report had put the quake's magnitude at 6.9.

In Taipei buildings swayed for up to 20 seconds when the quake hit but local television said there were no immediate reports of casualties or damage anywhere on the island.

Earthquakes frequently rattle Taiwan but most are minor and cause little or no damage.

However, a 7.6-magnitude earthquake in central Taiwan in 1999 killed more than 2,300 people.