A powerful earthquake with a preliminary magnitude of 8.1 rocked several remote islands off northern Japan on Wednesday, prompting thousands to evacuate to higher ground amid tsunami alerts.
Initial waves were small and there were no immediate reports of damage or injuries. Several thousand people on Japan's northernmost island of Hokkaido evacuated the coastline after the quake struck off its northern shores in an area claimed by both Japan and Russia. The alert was lifted after about three hours.
Japan's Meteorological Agency warned of tsunami about 2 meters tall or higher. The first wave was recorded at Nemuro port on Hokkaido hit at 9:29 p.m. (1759 IST), but was estimated at only 40 centimeters. A second wave of half that height was recorded about 15 minutes later and waves of diminishing height followed.
Officials several hours after the quake lifted the alert, but urged continued caution. Live footage from northern Japan after the first waves hit showed calm seas and lighted windows. Residents said they barely felt the quake.
An official from the town of Shibetsu on Hokkaido, Kiyoshi Takimoto, told public broadcaster NHK that about 4,000 of the town's 6,100 residents lived along the coast and had been told to flee to higher ground. Takimoto said he didn't notice the quake. The government set up an emergency task force at Japanese Prime Minister Shinzo Abe's office.
No damage or casualties were reported in Russia as a result of the quake, said Olga Shekhovtseva, chief spokeswoman for the Emergency Situations Ministry branch in the Sakhalin region, which includes the Kuril Islands.
The epicenter of the quake was in the Pacific Ocean east of Simushir, an uninhabited island in the Kurils, Shekhovtseva said. A tsunami alert was issued for the Kurils and Sakhalin, a large island between the chain and Russia's eastern coast, but was later lifted, she said.
Residents in the sparsely populated Kurils were warned of the threat but were not evacuated, she said, contradicting earlier Russian news agency reports that said residents were being evacuated from shoreline areas to safer ground.
The closest populated islands to the epicenter are Iturup and Kunashir to the south two of the disputed, Russian-held islands Russia calls the Southern Kurils and Japan calls the Northern territories and Paramushir in the north, off the Kamchatka peninsula.
Japan's Meteorological Agency said the quake struck about 390 kilometers east of Iturup known in Japan as Etorofu about 180 kilometers northeast of Hokkaido. It put the magnitude at 8.1, while the US Geological Survey estimated the magnitude at 7.8.
Nemuro official Masayuki Kikuchi said the city dispatched about 20 fire trucks and cars immediately after the tsunami alert to instruct coastal residents to evacuate to higher ground.
"There was no panic," Kikuchi said. "Residents made their way to higher ground, just like they do in our annual tsunami drill.