Analysts believe Japan's government and the nation's central bank may have conducted a yen-buying intervention worth about 5 trillion yen, or nearly 32 billion dollars, to stop the Japanese currency from falling sharply.

Market watchers suspect that the government and the Bank of Japan intervened without making an announcement, as the yen rapidly rebounded a few times on Monday. For example, it rose to the 154-yen level against the dollar after dropping to the 160-yen range.

The central bank's statistical report on its current accounts indicated on Tuesday that 7.56 trillion yen, or about 48 billion dollars, would be transferred from financial institutions to the government on Wednesday.

The private think tank, The Totan Research, estimates that about 5 trillion yen was used for the intervention.

Vice Minister of Finance for International Affairs Kanda Masato has repeatedly declined to comment on the matter. Statistics that will be issued by the Finance Ministry at the end of May will indicate whether any intervention was conducted.