A 6.8-magnitude quake that struck off Japan's northern coast over the weekend has triggered a small tsunami near the crippled Fukushima Daiichi nuclear plant.
Japan's Meteorological Agency said the temblor hit 10k below the sea surface off the coast of Fukushima at 4.22 am.
It rattled buildings in Tokyo, 250 km northwest of the epicentre which was in the city of Namie in Fukushima prefecture.
The quake set off in motion a small tsunami, measured 20 centimetres (8-inch) at Ishinomaki in Miyagi prefecture, and other locations in northeast Japan. No major damage was reported.
Tokyo Electric Power Co, operator of the stricken Fukushima Daiichi nuclear plant, reported no abnormalities at the facility following the quake.
"We have not seen any damage or any change in radiation gauges after the quake," news.com.au quoted TEPCO spokesman Masahiro Asaoka. "Today's operation has yet to start but we ordered workers to evacuate to high places," Asaoka added.
NHK reported three people were injured following the earthquake. Around 700 residents in the coastal prefectures of Fukushima, Miyagi, and Iwate evacuated.
Authorities lifted all tsunami and evacuation advisories to eight towns devastated by the March 2011 earthquake and tsunami two hours after the weekend quake.
JMA likewise issued a marine threat, warning residents strong currents were expected to continue. JMA ordered residents to "get out of the water and leave the coast immediately."
"Do not get in the sea or approach coasts until the advisory is cleared," the agency said in a statement.
Apart from Fukushima Daiichi nuclear plant, the Nuclear Regulation Authority likewise checked two other nuclear power plants, along with other nuclear facilities along the coast. No abnormalities were found on the two. Their reactors and fuel storage pools were being cooled safely, the NRA said.