A Tosoh Corporation tanker is sinking off the coast of Japan, national media reports.
Footage on Japanese television shows the deck of the tanker below the water off the southern coast of Yamaguchi prefecture.
The vessel is carrying a cargo of caustic soda, which has raised fears of localised pollution.
According to the Japanese coastguard the crew of four has been rescued.
Media reports name the tanker variously as the Hirokazumaru and Hirokazu Maru, neither of which are listed in shipping databases.
