Masses of green algae are again threatening to disrupt Olympic sailing at its base in the Chinese city of Qingdao.

Charlotte Glennie reports from Beijing the latest disruption comes just when Olympic sailing organisers thought they had their algae problem under control.

Tonnes of the green carpet-like weed have returned to within the confines of the fifty kilometre sailing course.

Troops had already removed well over a million tonnes of the algae from the competition venue and built barriers to keep it out.

But strong winds have blown it back in again.

Locals including hundreds of fishermen are continuing to battle against the weed, which is easily thick enough to clog a keel.

It's not known what causes the algae - China maintains it's a natural phenomenon, some environmentalists say it's the result of pollution.

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