Japanese authorities have flashed a warning of more aftershocks and tsunamis in the wake of this morning's mega quake.

The country's Meteorological Agency is urging people in quake-hit areas to evacuate to higher ground immediately for fear of more tsunamis.

The agency said that this morning's quake was hugely powerful, and people should brace themselves for possible major aftershocks.

They spoke after a wall of mud and water 33-ft high swept into coastal resorts of Japan - crushing everything in its path.

In Hawaii the threat of a major disaster has sparked panic as thousands flee, seeking high ground.

Massive waves are sweeping across the Pacific and, in some cases, they are higher than some of the islands they are expected to strike in the next few hours.

Japanese television has been showing footage of a giant whirlpool that has formed in the sea, sucking down boats and debris.

In the last few minutes an emergency has been declared at the Japanese nuclear power station nearest to the quake's epicentre.

Officials have declared a state of emergency after the cooling system at the plant in Fukushima failed. Reports say the nuclear power station is on fire.

Chief Cabinet Secretary Yukio Edano said the nuclear plant's systems had developed a mechanical failure in the system needed to cool the reactor after it was shut down following the quake. He said there was no radiation leak.

Mr Edano stressed the emergency was just a precaution. So far there has been no radiation leak at the Fukushima No. 1 power plant. He said the facility was not in immediate danger.

Officials appealed for people living near the facility to remain calm.



 The worst hit area has been the port city of Kamaishi where buildings and cars have been destroyed.

The quake, which measured 8.9 on the Richter scale, was the sixth largest in history and a tsunami warning has been sounded across the Pacific.

The Japanese Meteorological Agency issued a tsunami warming for the entire Pacific coast of Japan following the quake that struck about 125 kilometers off the eastern coast, at a depth of 10 kilometers.

Residents in the coastal areas have been urged to immediately evacuate to higher ground.   



The Pacific Tsunami Warning Center in Hawaii said a tsunami warning was also in effect for Russia, Marcus Island and the Northern Marianas.

It said a tsunami watch was issued for Guam, Taiwan, the Philippines, Indonesia and Hawaii.



Friday's massive quake was felt in Tokyo, where it shook buildings and caused several fires. 

Hawaii has already felt the force of the quake. Minutes after the Japanese disaster the island was hit by a 4.5 magnitude quake, but officials fear worst could be to come.

The first tsunami is expected to make land about 1.30pm UK time.