A strong earthquake has hit northeast Japan, jolting the area devastated by a quake and tsunami in March, but there were no immediate reports of damage or casualties and no tsunami warning.
The quake hit at 3.22am on Friday, local time (7.22pm, Thursday, Irish time) at a depth of 38km, with its epicentre 18km from Iwaki city in Fukushima prefecture, the United States Geological Survey said.
Fukushima is the site of the world's worst nuclear crisis in 25 years.
A March tsunami damaged an atomic plant there, which leaked radiation into the air, soil and sea, and forced thousands to leave their homes.
Tokyo Electric Power Company, operator of the crippled plant, said it had noticed no additional problems resulting from the latest quake, which also shook buildings in Tokyo.
TEPCO said that there was no damage to nuclear power plants from the earthquake.
The Japan Meteorological Agency measured the quake at 6.0 and its depth at 50km.
The tsunami generated by a 9.0-magnitude earthquake in March wiped out whole stretches of the country's northeast coast, leaving more than 20,000 people dead or missing.
Japan, located at the junction of four tectonic plates, experiences 20% of the strongest quakes recorded on Earth each year.
