Japanese stocks slumped almost 6 percent and to their lowest level in nearly two years and government bond futures rose on Tuesday after a fresh explosion rocked a stricken Japanese nuclear power station and workers were ordered to leave, a sign the situation may be getting more serious.

Stock had also dropped sharply on Monday after a massive earthquake and tsunami struck last week, leaving authorities struggling to tackle the situation and deal with the economic impact.

Three explosions, including one on Tuesday, have rocked the Fukushima Daiichi nuclear complex in Japan's ravaged northeastern coast since the magnitude 9.0 quake on Friday, raising serious questions about radiation leakage and longer term stability of the country's power supply.

All focus is on the nuclear crisis. In the situation where the crisis appears to be worsening, foreign investors, domestic fund operators are pulling out from Japanese shares, Hideyuki Ishiguro, a supervisor at Okasan Securities in Tokyo.

The broad TOPIX share index slid 5.6 percent to 799.02, the lowest since April 2009, after posting the biggest decline since the 2008 financial crisis on Monday on record volume.

The blue-chip Nikkei index dropped 5.1 percent to 9,136.09, led by selling in the futures market.

Ten-year Japanese government bond futures rose 0.28 point to 140.20, on the way to testing the high for the year hit on January 4 at 140.71.

Power companies were the biggest percentage losers in early trading, with shares of Kansai Electric Power and Chubu Electric Power, which both own nuclear plants, down 13 percent.

The yen edged down to 81.84 per dollar, relatively stable in the face of the equity market selloff. Traders were on alert for signs of Japanese investor capital repatriation that could push up the yen similar to what happened after the 1995 Kobe earthquake.

The dollar had touched a low around 80.60 on Monday, less than a yen from the record low of 79.75 yen touched in 1995 on EBS.

(Writing by Kevin Plumberg)