5.5-magnitude quake strikes near Japan's east coast: USGS

The moderate quake hit at a shallow depth of 11 kilometres (6.8 miles), 244 kilometres northeast of Tokyo, just after 5:00 am (2000 GMT).

Japan sits at the junction of four tectonic plates and experiences a number of relatively violent quakes every year. But rigid building codes and strict enforcement mean even strong tremors often do little damage.

On Wednesday a 6.3-magnitude quake hit 18 kilometres north-northeast of the town of Daigo, but there were no reports of injuries or damage.