TOKYO (REUTERS) - An earthquake with a preliminary magnitude of 6.3 hit off the coast of southern Japan on Friday (May 10) but no tsunami warning was issued and there were no immediate reports of damage, the Japan Meteorological Agency said.

The quake struck at 8.48am local time (7.48am Singapore time), with its epicentre off the coast of Miyazaki prefecture in the southern island of Kyushu at a depth of 20km, the agency said.

The US Geological Survey (USGS) put the magnitude of the quake at 6.4.

Japan's weather agency issued an emergency warning when the quake hit, prompting public broadcaster NHK to switch to special programming on the situation in the southern Kyushu region, including Miyazaki.

The initial quake was followed by another, of 5.1 magnitude, at 9.07am in the same area, according to the USGS.

Local media reported no damage in Miyazaki and its surrounding areas.

Japan sits at the junction of four tectonic plates and experiences a number of relatively violent quakes every year.