HONG KONG: Asian stock markets were broadly lower Monday, with Tokyo tumbling more than six percent after last week's devastating earthquake and tsunami as well as fears of a nuclear reactor meltdown.

The yen hit a four-month high before Japan's central bank pumped a record amount of money into financial markets, while nuclear plant operator TEPCO dived almost 24 percent.

Auto makers were also hammered after being forced to halt production in areas hit by the quake and tsunami, which it is feared may have killed over 10,000 people.

Tokyo's Nikkei stock index slumped 6.18 percent, or 633.94 points, to 9,620.49, its sharpest percentage loss since December 2008 at the height of the global downturn.

The index is also at its lowest level in four months.

Fears have been stoked as scientists worked to try to prevent a catastrophic meltdown at the Fukushima-Daiichi nuclear plant near Tokyo, which has been hit by explosions in two reactors while the cooling system in a third has failed.

TEPCO, the plant's operator, tumbled 23.57 percent.

Among carmakers, Toyota and Nissan plunged more than 10 percent at one point before recovering slightly.

At the end of the day Toyota was down 7.92 percent to 3,310 yen, Honda dropped 6.49 percent to 3,095, and Nissan lost 9.52 percent to 722 yen.

Sydney ended 0.40 percent, or 18.4 points, lower at 4,626.4 and Taipei closed 0.56 percent, or 47.80 points, off at 8,520.02.

However, steel companies and construction firms in Seoul, Shanghai and Tokyo got a boost on hopes for a pick-up in demand following the quake and tsunami.

Hong Kong closed 0.41 percent, or 96.10 points, higher at 23,345.88 and Shanghai added 0.13 percent, or 3.83 points, to end on 2,937.63.

Seoul staged a late rebound and closed 0.80 percent, or 15.69 points higher at 1,971.23.

As the Nikkei sank to lows not seen since November, the Bank of Japan injected 15 trillion yen ($182 billion) into the short-term money market to support confidence.

The fund provision is the largest ever by the central bank, which also held its key interest rate and increased an asset purchase scheme to boost the ailing economy.

"We will take every possible measure, including providing liquidity, to ensure the stability of financial markets and smooth settlements (of business deals)," a bank spokesman said.

The BoJ's cash injection pushed the yen back from a four month high versus the greenback.

The Japanese unit was at 80.60 to the dollar, its highest since November, as dealers bought into the safe-haven unit before easing back after the liquidity push flooded the market with cash.

In early European trade, the dollar was sitting at 81.79 yen against 81.91 in New York late Friday. The euro traded at 114.09 yen, compared with 113.89 in New York.

Prime Minister Naoto Kan said in a televised national address Sunday that the country was facing its worst crisis since the end of World War II.

"The current situation of the earthquake, tsunami and the nuclear plants is in a way the most severe crisis in the 65 years since World War II," he said.

Oil slipped on concerns that demand from Japan will drop off.

New York's main contract, light sweet crude for delivery in April, dipped $1.33 to $99.83 per barrel, and Brent North Sea crude for April delivery was down $1.81 to $112.03 in the afternoon.

However, Chen Xin Yi, commodities analyst for Barclays Capital, said that prices were likely to pick up later as fuel oil imports rise due to the lost nuclear power capacity.

Gold closed at at $1,427.00-$1,428.00 an ounce in Hong Kong, up from Friday's close of $1,415.00-$1,416.00.

In other markets:

-- Singapore closed down 0.41 percent, or 12.63 points, at 3,030.86.

DBS Bank rose 0.70 percent to Sg$14.46, while SingTel fell 0.34 percent to Sg$2.95.

-- Kuala Lumpur closed flat, edging down 0.27 points to 1,495.35.

State-owned power firm Tenaga Nasional shed 2.70 percent to 6.03 ringgit, Petronas Gas was down 2.40 percent at 11.24 while glove-maker Top Glove rose 3.30 percent to 5.05.

-- Jakarta ended 0.78 percent, or 27.61 points, higher at 3,569.84.

-- Manila finished 0.14 percent, or 5.65 points, lower at 3,918.70.

Aboitiz Equity Ventures was down 1.0 percent at 41 pesos, Metropolitan Bank & Trust fell 1.3 percent to 62.05 and Philippine Long Distance Telephone lost 0.9 percent to 2,180.

-- Wellington ended 0.64 percent, or 21.64 points, lower at 3,361.20.

Telecom fell 2.7 percent to NZ$1.99, insurer Tower dived 3.8 percent to NZ$1.79 and Air New Zealand slipped 1.65 percent to NZ$1.19 while Contact Energy lost 0.50 percent to NZ$5.94.

-- Bangkok rose 1.57 percent, or 15.83 points, to 1,022.89.

Banpu jumped 30.00 baht to 750.00 and PTT Plc added 6.00 baht to 349.00.

-- Mumbai closed 1.46 percent, or 265.39 points, higher at 18,439.48.