A tsunami alert has been lifted for a small group of Japanese islands after the waves hit but caused no damage.
The alert followed a strong undersea earthquake 200km (125 miles) east of the country.
Waves up to 30cm (12 inches) high hit the Izu-shoto islands, Japan's Meteorological Agency said, an hour after the 6.8 magnitude quake.
Earthquakes are common in the region and the JMA issues an average of two tsunami alerts a year.
Correspondents said that the earthquake, which struck at 1511 (0611 GMT), was hardly felt in Japan's major cities.
The height of tsunami waves at sea is often less than one metre but they can grow dramatically as they approach land.
Coastal areas in the Indian Ocean were devastated by a tsunami off Indonesia on 26 December which caused more than 160,000 deaths.