At least seven dead as chemical tanker Keoyoung Sun, carrying 1,000 tons of acid, capsizes during a storm off the coast of Japan

SEVEN people have been declared dead after a South Korean-flagged chemical tanker capsized off the coast of Japan.

The ship, which was carrying almost 1,000 tons of acid, capsized during a storm at sea.

The Japanese coast guard rushed to help the 11-member crew, but only nine have been found so far.

They confirmed that one member of the crew is still alive, while the condition of the remaining sailor is unknown.

Rescuers are still searching for two others who were on board when disaster struck this morning.

Those aboard the Keoyoung Sun sent out a distress call as the tanker struggled off the coast of a Japanese island.

By the time the Coast Guard reached them, it had completely capsized.

Dramatic images of NHK shows the boat being tossed around in choppy waters.

And a rescue helicopter hovering above the water takes a member of the crew to safety.

Waves in the sea reached a height of 3.5 meters during the storm, swallowing the boat.

Officials said the tanker was carrying 980 tons of acrylic acid.

No leak has been discovered yet, but officials are looking at what they might need to do if it is.

The crew consisted of two South Korean, one Chinese and eight Indonesian workers.

The boat was anchored off the coast of Mutsure Island, near Honshu, at the time.

Honshu, Japan’s main island, is about 1,000 kilometers from Tokyo.

The crew took shelter from bad weather when the tanker began to overturn, prompting them to make a distress call.

It is not entirely clear how the ship capsized.

Environmental protection measures could be taken if acrylic acid leaked from the tanker.

The chemical is used in plastics, resins and coatings and can irritate human skin and eyes, according to the U.S. Environmental Protection Agency.