Countries and aid groups are offering to help Japan's rescue efforts.
U.S. President Barack Obama says the U.S. stands "ready to help the Japanese people in this time of great trial". The U.S. military in Japan has opened its airfields to commercial aircraft in the disruption of operations at Japanese airports, CNN quoted the Pentagon as saying.
The United Nations says 30 international search and rescue teams are on alert to go to Japan to provide assistance.
South Korea is initially sending 40 emergency rescue officials who are on standby to fly in by government plane when they get clearance, its foreign ministry said.
Chinese earthquake rescuers are "fully prepared" to go to Japan to join earthquake relief work if needed, state media quoted the country's top seismological official Chen Jianmin as saying.
Thailand will offer 5 million baht ($165,00) aid to Japan and will consider giving more when the extent of the damage is known, Thai Foreign Ministry spokesman Thani Thongpakdi said.
British Foreign Secretary William Hague said Britain was in contact with the Japanese government and he has asked the country's ambassador in Tokyo to offer all assistance
Indonesia had expected tsunami waves to hit the northern coastal areas of Sulawesi, the Moluccas and Papua islands at 1130 GMT, but by 1200 GMT it had not been felt, an Indonesian official said
Power cut to four million homes in and around Tokyo. Several fires blaze in Tokyo. Many sections of Tohoku expressway serving northern Japan damaged. Major fire at Chiba refinery near Tokyo.
Bullet trains to the north of the country stopped. The government was to dispatch 900 rescue workers to stricken regions.
Tokyo's Narita international airport resumes some outbound flights after earlier closing, halting flights and evacuating passengers. Tokyo underground, suburban trains halted. Sendai airport in the north flooded. All Japanese ports closed and discharging operations halted, shippers report.
Eight military planes scrambled to survey damage. Prime Minister Naoto Kan asks people to remain calm and orders the military to do their utmost to act. Cabinet to meet. The government says more tsunami possible.
