* Latest explosion caused by hydrogen
* USGS upgrades magnitude of Friday's quake to 9.0
* UN nuclear chief says repeat of Chernobyl unlikely
* More than 10,000 feared killed by quake, tsunami
* Futures point to Japan shares falling further
By Taiga Uranaka and Ki Joon Kwon
FUKUSHIMA, Japan, March 15 A fresh explosion
rocked a damaged Japanese nuclear power plant on Tuesday where
engineers have been pumping sea water into a reactor to prevent
a catastrophic meltdown in the wake of a devastating earthquake
Japan's nuclear safety agency said Tuesday's explosion at
the plant's No.2 reactor was caused by hydrogen. There was no
immediate word on damage, but Jiji news agency quoted the trade
ministry as saying radiation levels remained low after the
blast, the third at the plant since Saturday.
Japan has asked the United States for more equipment to help
cool reactors at the Fukushima nuclear complex, which was hit on
Monday by a dangerous drop in cooling water levels that exposed
fuel rods in the No. 2 reactor.
The full extent of the destruction wreaked by Friday's
massive quake and tsunami that followed it was still becoming
clear, as rescuers combed through the region north of Tokyo
where officials say at least 10,000 people were killed.
"It's a scene from hell, absolutely nightmarish," said
Patrick Fuller of the International Red Cross Federation from
the northeastern coastal town of Otsuchi.
Prime Minister Naoto Kan said Japan was facing its worst
crisis since World War Two and, with the financial costs
estimated at up to $180 billion, analysts said it could tip the
world's third biggest economy back into recession.
The U.S. Geological Survey upgraded the quake to magnitude
9.0, from 8.9, making it the world's fourth most powerful since
Car makers, shipbuilders and technology companies worldwide
scrambled for supplies after the disaster shut factories in
Japan and disrupted the global manufacturing chain.
Japanese stocks were expected to fall further on Tuesday,
after Nikkei futures traded in Chicago fell 6.15 percent
to be 70 points below the Osaka close.
Tokyo's TOPIX index closed down more than 7.5
percent on Monday, wiping $287 billion off market capitalisation
in the biggest fall since the height of the global financial
crisis in 2008. Insurers' shares fell for a second day in London
and New York, as world stocks slid to a six-week low.
The fear at the Fukushima complex, 240 km (150 miles) north
of Tokyo, is of a major radiation leak after the quake and
tsunami knocked out cooling systems. The complex has seen
explosions at two of its reactors on Saturday and Monday.
The worst nuclear accident since the Chernobyl disaster in
Ukraine in 1986 has drawn criticism that authorities were
ill-prepared and revived debate in many countries about the
safety of atomic power.
Switzerland put on hold some approvals for nuclear power
plants and Germany said it was scrapping a plan to extend the
life of its nuclear power stations. The White House said U.S.
President Barack Obama remained committed to nuclear energy.
Yukiya Amano, head of the International Atomic Energy
Agency, said the reactor vessels of nuclear power plants
affected by the disaster remained intact.
"The nuclear plants have been shaken, flooded and cut off
from electricity," he told a news conference. But "the reactor
vessels have held and radioactive release is limited."
Amano, a veteran Japanese diplomatic, added that a
Chernobyl-style disaster was "very unlikely".
An explosion at the Soviet Chernobyl plant sent radioactive
fallout across northern Europe.
Whilst the Fukuskima plant's No.1 and No.3 reactors both
suffered partial fuel rod meltdowns, operator Tokyo Electric
Power Co (TEPCO) said the No. 2 reactor was now the
A sudden drop in cooling water levels when a pump ran out of
fuel had fully exposed the fuel rods for a time, an official
said. This could lead to the rods melting down and a possible
TEPCO said it had resumed pumping sea water into the reactor
early on Tuesday.
"This is nothing like a Chernobyl," said Murray Jennex, a
nuclear expert at San Diego State University. "At Chernobyl you
had no containment structure -- when it blew, it blew everything
straight out into the atmosphere."
Nonetheless, the government warned those still in the 20-km
(13-mile) evacuation zone to stay indoors. TEPCO said 11 people
had been injured in the blast.
U.S. warships and planes helping with relief efforts moved
away from the coast temporarily because of low-level radiation.
The U.S. Seventh Fleet described the move as precautionary.
South Korea, Hong Kong, Singapore and the Philippines said
they would test Japanese food imports for radiation.
France's ASN nuclear safety authority said the accident
could be classified as a level 5 or 6 on the international scale
of 1 to 7, putting it on a par with the 1979 U.S. Three Mile
Island meltdown, higher than the Japanese authorities' rating.
Japan's nuclear safety agency has rated the incidents in the
No.1 and No.3 reactors as a 4, but has not yet rated the No. 2
About 850,000 households in the north were still without
electricity in near-freezing weather, Tohuku Electric Power Co.
said, and the government said at least 1.5 million households
lack running water. Tens of thousands of people were missing.
"The situation here is just beyond belief, almost everything
has been flattened," said the Red Cross's Fuller in Otsuchi, a
town all but obliterated. "The government is saying that 9,500
people, more than half of the population, could have died and I
do fear the worst."
Kyodo news agency reported that 2,000 bodies had been found
on Monday in two coastal towns alone.
Whole villages and towns have been wiped off the map by
Friday's wall of water, triggering an international humanitarian
effort of epic proportions.
"When the tsunami struck, I was trying to evacuate people. I
looked back, and then it was like the computer graphics scene
I've seen from the movie Armageddon. I thought it was a dream .
it was really like the end of the world," said Tsutomu Sato, 46,
in Rikuzantakata, a town on the northeast coast.
In Tokyo, commuter trains shut down and trucks were unable
to make deliveries as supermarket shelves ran empty.
Estimates of the economic impact are only now starting to
Hiromichi Shirakawa, chief economist for Japan at Credit
Suisse, said in a note to clients that the economic loss will
likely be around 14-15 trillion yen ($171-183 billion) just to
the region hit by the quake and tsunami.
Even that would put it above the commonly accepted cost of
the 1995 Kobe quake which killed 6,000 people.
The earthquake has forced many firms to suspend production
and shares in some of Japan's biggest companies tumbled on
Monday, with Toyota Corp dropping almost 8 percent.
Global companies from semiconductor makers to shipbuilders
faced disruptions to operations after the quake and tsunami
destroyed vital infrastructure, damaged ports and knocked out
"The earthquake could have great implications on the global
economic front," said Andre Bakhos, director of market analytics
at Lec Securities in New York. "If you shut down Japan, there
could be a global recession."
The Bank of Japan offered a combined 15 trillion yen ($183
billion) to the banking system earlier in the day to soothe
(Additional reporting by Nathan Layne, Risa Maeda and Leika
Kihara in Tokyo, Chris Meyers and Kim Kyung-hoon in Sendai,
Fredrik Dahl and Michael Shields in Vienna, Noel Randewich in
San Francisco and Miyoung Kim in Seoul; Writing by Alex