According to a statement by the Japanese finance ministry
It says that senior officials from the BOJ, Ministry of Finance and the Financial Services Agency met today to exchange views on global financial markets. The meeting is also said to include Japan's top currency diplomat, Yoshiki Takeuchi.
For some context, meetings like these are not uncommon in Japan and are held from time to time especially when authorities feel that there has been excessive market volatility.
I reckon they probably met up to discuss about the Fed decision and its implications for the Japanese yen this time around. I wouldn't view this as an emergency meeting to review any immediate action/intervention.
