A 6,2-magnitude earthquake hit near the city of Iwaki in Japan on Monday, the United States Geological Survey (USGS) said, revising it to a slightly stronger quake than it initially reported.
Strong earthquakes have also hit Indonesia and India since Sunday, killing at least three people in central Indonesia.
The quake in Japan was centred 68km north-east of Iwaki, Honshu, and struck at 1.51pm GMT at a depth of 27km, the USGS said.
The agency earlier said the quake was a magnitude six, and was centred 72km north-east of Iwaki, striking at a depth of 39k.
In central Indonesia, at least three people were killed and 45 injured when powerful earthquakes struck off the coast of Sumbawa island on Sunday, a Health Ministry official said on Monday.
Several buildings, including a health clinic, collapsed in the island’s Bima district, said Rustam Pakaya, head of the ministry’s crisis centre. "The casualties are likely to increase and we are still assessing the situation."
The quakes affected the eastern side of Sumbawa island, a rugged volcanic island that gets fewer tourists than neighbouring Lombok and Bali.
The first quake of magnitude 6,7 struck 48km north-west of Raba in Sumbawa just after midnight, an official at the country’s meteorological agency said. A second quake of 6,8 struck about four hours later in the same area, triggering a brief tsunami warning, the official added. The USGS put the second quake at magnitude 6,3.
An earthquake measuring six also struck off the coast of Sumatra island in the early hours of Monday, about 100km south-west of Mukomuko in Bengkulu, the local meteorology agency said. There was no tsunami warning. On Sunday, a quake with a 6,2 magnitude hit the same area.