SINGAPORE (AFX-ASIA) - The yen extended its gains against the dollar in midday trade as investors moved to safer currencies after the US attacks against Taliban targets in Afghanistan, dealers said. "The strength in the yen is a consequence of the US military action which is causing the US dollar to weaken substantially while currencies which are considered a safe haven are getting a boost," a foreign bank dealer said. He added however that trading volume was very thin, with very few "substantive deals so far".