TOKYO—A series of powerful tremors Monday rattled a central Japanese region still reeling from last month’s earthquake, slightly injuring eight people just as the last schools shut by the tragedy reopened.
Six tremors, with the strongest measuring 5.9 on the Richter scale and felt in Tokyo, struck within three hours starting at 11:15 a.m. (0215 GMT) in Niigata prefecture, the Meteorological Agency said.
The quakes were so powerful that some frightened children ran out of their classrooms on a day that was supposed to mark the return to normal at schools.
“Because of the aftershocks, some schools will let kids go home earlier,” a local education official said.
The official said 35 schools reopened Monday, the last of the prefecture’s 832 public elementary and junior high schools to resume classes since the October 23 earthquake which killed 39 people.
A tremor Monday collapsed the walls of a building, hurting five children and a woman, but a spokesman for the Niigata fire department said their injuries were not believed to be life-threatening.
Elsewhere a 75-year-old woman fell from her motorbike and a 68-year-old man was rescued after a fall, officials said.
“I was so shocked. But everything’s OK as all my things were already broken by the previous quakes,” a woman in her 20s told national broadcaster NHK.
The October 23 initial tremor registered 6.8 on the Richter scale and was followed by hundreds of aftershocks.
“I am so sick of aftershocks,” a woman in her 50s told the station. “I just wanted to go home.”
Last month’s earthquake was Japan’s deadliest in nine years and also injured 2,600 people. The initial tremor derailed Japan’s famed bullet train for the first time.
During the latest tremors the bullet train to Niigata, 200 kilometers northwest of Tokyo, was halted as a precaution but should be running at normal speed by the end of Monday, a railway spokesman said.
The Meteorological Agency warned Niigata residents to remain cautious for at least a month.
The strong tremors were caused because a geological fault in the area appears to have been pushed upward by compression, said Masahiro Yamamoto, the agency’s chief monitor for earthquakes and tsunami tidal waves.
“We are seeing relatively frequent aftershock activities. Continued caution is necessary,” he told reporters.
“We expect the aftershocks will eventually die down after going through phases of frequent and then slow activity,” he added.