Construction of a sea barrier off eastern China to keep algae out of the Olympic sailing venue was hindered by heavy fog on Tuesday.

As of mid-day, 19,000 meters of the 32,000-meter enclosure had been finished, but workers had to return to shore in the afternoon after fog reduced visibility to about 20 meters, according to Zhao Han, vice head of the Qingdao Maritime Affairs Bureau.

The fog persisted into the evening, preventing work from resuming.

The government planned to complete the enclosure on Tuesday, according to a press conference by the Qingdao city government on Monday.

About 100 ships have been working to build the enclosure every day.

The Qingdao government has vowed to clear up the venue before July 15.

In the past two weeks, more than 130,000 soldiers and volunteers have been working to remove the algae, and the coverage of the green weed has shrunk to 1.37 percent from 32 percent over the past 10 days.

(Xinhua News Agency July 9, 2008)