A dark red tide has made its way onto the coast of northern Zhejiang Province, Zhejiang Provincial Marine and Fishery Bureau announced on Thursday.

The red tide covered about 4,000 square kilometers of sea on Monday in Zhoushan, a city in northern Zhejiang, but within 24 hours had extended to 7,000 square kilometers on Wednesday.

Large red tides also showed up near Wenzhou, a city in southern Zhejiang Province, on Tuesday. It covers about 340 square kilometers and continues to grow.

Preliminary investigations show that the "redness" actually indicates the presence of a kind of poisonous algae, which could kill shellfish.

Provincial authorities have suspended shellfish fishing in affected areas, said Li Dongyong, deputy-director of Zhejiang Provincial Marine and Fishery Bureau.

The red tide is expected to persist for a few more days since current weather conditions are favorable for the growth of the algae.

(Xinhua News Agency June 3, 2005)