A powerful 7.6-magnitude earthquake struck off northern Japan on Monday, triggering a tsunami of up to 15 inches in coastal communities in the region, the Japanese Meteorological Agency said.

The agency said the quake struck just east of Aomori, the northernmost prefecture of Japan's main Honshu island, and just south of Hokkaido island. It said a tsunami of 40 centimeters (about 15.75 inches) struck the Hokkaido prefecture town of Urakawa and the Aomori prefecture port of Mutsu Ogawara.

Several people were injured at a hotel in the Aomori town of Hachinohe, public broadcaster NHK reported.

The U.S. National Tsunami Warning Center said there was no tsunami danger for the U.S. West Coast, Canada's British Columbia or Alaska.

Japanese Prime Minister Sanae Takaichi, in brief comments to reporters, said the government set up an emergency task force to urgently assess the extent of damage. "We are putting people's lives first and doing everything we can," she said.

Nuclear power plants in the region were conducting safety checks, NHK reported.

The quake was also felt in the northern hub of Sapporo, where alarms rang on smartphones to alert residents.

A reporter for NHK in Hokkaido described a horizontal shaking of around 30 seconds that made him unable to keep standing as the earthquake struck.

Japan sits on top of four major tectonic plates along the western edge of the Pacific "Ring of Fire" and is one of the world's most tectonically active countries.

The archipelago, home to around 125 million people, experiences around 1,500 jolts every year.

The vast majority are mild, although the damage they cause varies according to their location and depth below the Earth's surface.

This is a breaking news story. Check back for updates.