A tsunami warning for residents along Japan's eastern coast was withdrawn Saturday after residents fled to higher ground amid fears that a powerful wave was headed their way.
Warnings were also issued for Hawaii and Alaska, all triggered by an 8.2 magnitude earthquake.
More than two years after a devastating tsunami triggered by an earthquake in the Indian Ocean killed at least 230,000, coastal residents are still on alert against potential repeats of the calamity.
But by late Saturday, over three hours after the quake, the largest wave to hit was a 40-centimetre tidal surge along Chichi-jima, a Pacific island about one 1,000 kilometres south of Tokyo.
Earlier, in Nemuro on Japan's northeastern coastal, a 10-centimetre tidal swell was recorded. Higher tides were also recoded in other Japanese coastal towns.
The Saturday quake struck at about 1:24 p.m. local time, almost 500 kilometres east of Etorofu, the largest in a chain of four disputed islands known as the Northern Territories in Japan, and the Kuril islands in Russia.
The quake struck 30 kilometres beneath the surface, The Associated Press reports.
It was initially estimated to have a magnitude of 8.3, but the rating was later dropped to 8.2 by the Japanese agency, matching estimates by the U.S. Geological Survey.
There were no reported injuries due to the earthquake, but residents of Hokkaido, Japan's northern island, were warned that higher than usual waves could hit the northeastern coast. Officials than ordered the evacuation of 85,000 residents of 22 towns along the coast.
Thousands of people observed the warning, gathering in community centres away from the coast, Disaster prevention official Haruyuki Komachi told AP.
Roads leading to the coast were also closed off and some train routes were shut down as a precaution.
However, as the threat subsided, the warnings were reduced to advisories, then cancelled outright for Hokkaido's northern coast.
Some municipalities then lifted evacuation orders, but by late Saturday advisories were still in place in some other parts of the island.
"The tidal change so far seems rather small, but a bigger one may come hours later," Komachi said. "So we have to stay vigilant into the night in case a second or a third ones come in bigger waves."
Elsewhere, tsunami warnings were also lifted for Hawaii and Alaska, where dozens of residents on two Aleutian islands had fled to underground shelters.
In the Philippines, residents on the eastern seaboard were advised to watch for sea level changes, and about 4,000 people in the northern province of Isabella were evacuated.
Tsunami warnings are issued when there is an imminent threat of a tsunami. Tsunami watches are issued as an advance alert to areas that could be impacted by a tsunami.
Temblors of magnitude 7 are generally classified as major earthquakes, capable of widespread, heavy damage.
In Japan, Tokyo University seismologist Yoshinobu Tsuji warned that high waves could still hit the region, and residents should remain vigilant.
On Dec. 26, 2004, a magnitude-9.0 earthquake off Indonesia's Sumatra island unleashed giant waves that fanned out across the Indian Ocean at jetliner speeds, leaving at least 230,000 dead and millions of homeless in its wake.
With files from The Associated Press
