A magnitude 6.6 earthquake has hit northern Japan near a major city.

The US Geological Survey said it struck the island of Hokkaido around 3am local time on Thursday and had a depth of 21 miles.

The quake’s epicentre is about 17 miles east of the city of Tomakomai, which has a population of about 175,000, and 40.3 miles southeast of Sapporo – a major metropolitan area of 1.9 million people.

The Kyodo news service reported in Tokyo, the central government set up a liaison unit at the crisis management centre of the prime minister’s office to gather information on the earthquake.

Chief Cabinet Secretary Yoshihide Suga said Prime Minister Shinzo Abe instructed officials to ascertain the extent of damage and extend a helping hand to those affected.

The quake triggered a blackout across a wide area in Hokkaido.

It also affected telephone service and television broadcasting in Sapporo.