The United States Geological Survey said the magnitude 7.6 quake struck at 1415 GMT off Misawa on Japan's Pacific coast, at a depth of 53 kilometres (33 miles).

The Japan Meterological Agency issued a tsunami warning, with a first wave hitting a port in the northern region of Aomori, where Misawa is located, at 11:43 (1443 GMT).

At 11:50 pm, another wave reached the town of Urakawa town in the Hokkaido region, the agency said.

Both waves measured 40 centimetres (16 inches), it added.

Public broadcaster NHK cited a hotel employee in the city of Hachinohe in Aomori as saying there had been some injuries, with live footage showing shattered glass fragments scattered across roads.

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.

The meteorological agency earlier warned a tsunami of up to three metres (10 feet) was expected to hit Japan's Pacific coast.

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.