Japan earthquake and tsunami - latest updates: Monday
10.40pm: A reactor at a power plant in quake-hit Fukushima has lost all its cooling capability, Japan's Nuclear and Industrial Safety Agency says.
9.23pm: US helicopters flying missions about 96km north of the damaged Fukushima reactors were coated with radioactive dust that had to be washed off, the New York Times has reported.
8.20pm: China has expressed condolences to its regional rival Japan for the loss of life resulting from Friday's earthquake and tsunami.
Premier Wen Jiabao said Monday at the end of China's annual legislative session that a Chinese rescue team was in Japan, where thousands are estimated to have died.
Wen told a news conference: "I want to use today's opportunity to extend our deep condolences over the lost lives in this disaster and express our sincere sympathy to the Japanese people".
7.46pm: A magnitude 6.1 aftershock has been felt in northeastern Japan, the United States Geological Survey reports.
7.28pm: The Tokyo stock market has plunged on its first business day after an earthquake and tsunami of epic proportions laid waste to cities along Japan's northeast coast.
The benchmark Nikkei 225 stock average dived 646.32 points, or 6.3 per cent, to 9605.11 - its lowest level in four months.
6.34pm: Automaker Toyota plans to halt operations at all of its factories in Japan.
Toyota has announced that it will stop production at its 12 factories across the country.
5.50pm: Japan's nuclear safety agency says six workers were injured in today's explosion. They were all conscious.
5.12pm: Eleven people were injured in the blast at Fukushima nuclear plant, Kyodo News reports.
4.50pm: Some 2,000 bodies were found on two shores in Miyagi Prefecture following Friday's devastating earthquake and massive tsunami.
3.30pm: Japanese media report another hydrogen explosion has taken place at the Fukushima nuclear facility.
3.14pm: Japanese television station NHK reports a three to five-metre change in the sea level has been detected in north of country.
2:40pm: A magnitude 5.8 quake has struck 140 kilometres northeast of Tokyo, shaking tall buildings in the city.
Authorities did not issue a tsunami alert and there were no immediate reports of damage or casualties.
1.25pm: Bank of Japan injects 7 trillion yen (NZ$115 billion) into short-term money markets following quake.
1.23pm: Japan's key Nikkei sharemarket index has fallen five per cent in early trading today on quake fears.
1.09pm: Experts say that "tsunami overlap" increased the destructive power of the sea surge after Friday's earthquake.
As the fault rupture was 500km long in a north-south direction, "tidal waves hit the coastal area from different directions and crossed over each other, increasing [the tsunami's] destructive power", Tomoya Shibayama, professor of ocean engineering at Waseda University, told the Yomiuri Shimbun newspaper.
"They also became higher after currents threw them back and forth against the sea floor in coastal areas where the water was more shallow," he said.
12.27pm: Japan Nuclear and Industrial Safety Agency official says there's no need to be overly alarmed by radiation rise.
Naoki Kumaga said radiation at the Fukushima plant was higher than legal limits but they would be much higher if the reactor was on the verge of a meltdown.
12.17pm: Wall Street Journal reports Japan could be facing biggest disaster recovery bill in history.
11.51am: New Zealand officials say there continue to be no reports of Kiwis injured or killed in Japan.
11.13am: Radiation levels have again risen above allowable levels at the Fukushima nuclear plant, Kyodo News reports.
11.10am: Japanese authorities say that radioactivity levels at the site boundary of the Onagawa nuclear power plant have returned to normal levels.
The current assumption of the Japanese authorities is that the increased level may have been due to a release of radioactive material from the Fukushima Daiichi nuclear power plant.
10.51am: Japanese officials say radiation levels have dropped off at Fukushima reactor that exploded at the weekend.
10.45am: Japanese with power asked to conserve it as companies say rolling outages will begin today.
10.13am: Japan has been rocked by more than 250 aftershocks since Friday's magnitude 9 earthquake.
9.23am: Australia's Foreign Minister Kevin Rudd says entire international community is worried by nuclear crises in Japan.
8.50am: NZ has been assured our search and rescue team in Japan will be kept safe from potential radiation.
8.07am: Japanese weather agency says a volcano in southern Japan is spewing ash and rock into the atmosphere.
The volcano is on Kyushu island, about 950 miles from the epicentre of Friday's magnitude 9.0 earthquake and tsunami, which devastated much of the country's northeastern coast.
8.06am: Japanese officials say cooling system at Tokai nuclear plant north of Tokyo is now working again.
7.46am: The remainder of New Zealand's search and rescue personnel have arrived in Japan.
The advance team arrived yesterday and the last contingent of personnel arrived this morning, Foreign Affairs Minister Murray McCully said.
New Zealand authorities are urging Kiwis in Japan to get in contact, or contact friends or family so they can get a better idea of how many are there and their situation. If calling from overseas, call +64 439 8000. If you are in New Zealand it is 0800 432 111.
7.37am: 310,000 people have been evacuated from Japan's northeastern coast following the tsunami and crises at nuclear plants in the region.
6.30am: The cooling system pump has stopped at the Tokai No.2 nuclear power plant in Japan's Ibaraki prefecture, Kyodo news has reported.
The plant, located about 120km north of Tokyo, had suffered a nuclear accident in 1999.
Authorities admitted there may have been a partial meltdown at the stricken Fukushima plant - however they are not able to get close enough to the reactor to confirm this.
6.16am: A state of emergency has been declared at Onagawa nuclear power plant.
Authorities say a partial meltdown could be in progress in two reactors, but they can't confirm this.
Over 200,000 people have been evacuated from around the Fukushima reactors.
US aircraft carrier USS Ronald Reagan has begun rescue operations off the coast of Japan.