¡¡TOKYO, Oct. 12 (Xinhuanet) -- Three workers were seriously injured Tuesday in an explosion at a shipyard in Tadotsu, west Japan's Kagawa Prefecture, the national police agency said.

    The 2:45 p.m. (0545 GMT) blast occurred inside a freighter but no fire was reported. The three men received burns and were taken to a nearby hospital, where they are being treated in an intensivecare unit.

    According to the agency, a fourth worker was taken to the hospital but his condition was not immediately known.

    The cause of the explosion is under investigation. Enditem