A strong earthquake hit off the eastern coast of central Japan on Sunday, rattling buildings across a broad swath of the country, including the crowded Tokyo capital.
There were no immediate reports of damage or casualties, and the government said there was no danger from tsunamis.
The quake had an initial estimated magnitude of 6.6, according to the Japan Meteorological Agency.
It hit at 0808 GMT on Sunday, or 5:08 p.m. local time.
The earthquake was centered about 50 miles (80 kilometers) off the eastern coast of central
Fukushima Prefecture, and struck at a depth of 25 miles (40 kilometers).
It was strong enough to gently sway buildings in Tokyo, about 185 miles (300 kilometers) to the southwest, for several seconds.
Television images from the regions near where the quake was centered showed no damage, with cars driving normally.
Japan's early warning system predicted the earthquake just before it hit, with public broadcaster NHK interrupting a sumo match to warn residents to take cover.
The country is one of the world's most earthquake-prone countries. In 1995, a magnitude-7.2 quake in the western port city of Kobe killed 6,400 people.