The Bank of Japan injected ¥2.5 trillion into markets Sept. 16 as Japan scrambled to calm fears about a financial crisis after U.S. investment bank Lehman Brothers filed for bankruptcy.

Toshimitsu Motegi KYODO PHOTO

Financial Services Minister Toshimitsu Motegi sought to allay fears by saying the impact on Japanese financial institutions was limited.

"So far, we haven't confirmed any signs that Japanese financial institutions are seriously affected," he said, adding officials will "raise alert levels" to closely monitor the situation.

Japan's central bank pumped ¥1.5 trillion into money markets even before trading began to prepare for possible volatility in the wake of news that Lehman had filed for bankruptcy protection in the United States on Sept. 15. Its Japanese unit also filed for bankruptcy protection at a Tokyo court Sept. 16 under the Japanese civil rehabilitation law, with debt totaling about ¥3.43 trillion.

That makes it the second-largest bankruptcy in Japan since World War II, according to Tokyo Shoko Research Ltd.

On Sept. 16, the BOJ added another ¥1 trillion to money markets.

The BOJ issued a statement vowing to take measures to maintain stability in the country's financial markets.

"The Bank of Japan will closely watch developments surrounding the latest U.S. financial institutions and their impact, and will continue to take appropriate measures to maintain smooth settlement and stability in the financial market," BOJ Gov. Masaaki Shirakawa said in a statement.