Seven people have been pronounced dead after a South Korean chemical tanker capsized off an island in south-western Japan, the coast guard said.

The dead were among nine people initially rescued from the Keoyoung Sun tanker after it sent a distress call during rough weather near Japan’s Mutsure Island.

The coast guard is still searching for two more people who were on the chemical tanker.

The island is just off the southwestern end of Japan’s main island of Honshu, about 620 miles from Tokyo.

The ship was completely capsized by the time rescuers arrived at the scene, the coast guard said.

Footage on NHK television showed the ship completely upside down, with a rough sea washing over its red underside.

The ship was carrying a South Korean captain, and its crew included another South Korean national, a Chinese national and eight Indonesians, according to the coast guard.

The tanker was carrying 980 tonnes of acrylic acid, officials said. No leak has been detected, and officials are studying what environmental protection measures may be needed in case there is a leak.

Acrylic acid is used in plastics, resin and coatings and can irritate the skin, eyes and mucous membranes, according to the US Environmental Protection Agency.