An earthquake with a magnitude of 6.0 shook eastern Japan, injuring at least 27 people, rattling buildings and disrupting train and plane services.
Japan's Meteorological Agency said there was no danger of tsunami waves from the quake, which struck at 4:35 p.m. local time on Saturday.
The quake was the strongest to rock Tokyo in more than a decade and left a number of people trapped in elevators.
The meteorological agency said the quake was centred about 90 kilometres underground in Chiba prefecture, just east of Tokyo.
About 27 people in the region were injured, the Kyodo News agency reported.
Tokyo's Narita International Airport shut down briefly and some trains between Tokyo and western communities were temporarily suspended.
A quake of magnitude 5 or more can damage homes and other buildings if it's situated in a heavily populated area.
Earthquakes are common in Japan, which lies in one of the world's most seismologically active regions.
A magnitude 7.0 quake with a series of aftershocks shook southern Japan in March, killing one person and injuring more than 400 others.
- FROM MARCH 20, 2005: Japanese quake injures more than 400, kills 1
In the worst recent incident, a series of quakes struck in late October and killed 39 people. The quakes cut water and gas services in Niigata prefecture, about 250 kilometres north of Tokyo, and left more than 46,000 people living in emergency shelters.
- FROM OCT. 24, 2004: Deadly earthquakes strike Japan
That quake was the most devastating in Japan since 1995, when a quake with a magnitude of 7.2 killed more than 6,000 people in Kobe.