The women's semi-finals in the kayak and the double canoe final were put back to Friday after violent storms battered the venue at Shunyi, just to the north of Beijing.

Only semi-finals of canoe doubles were completed before weather worsened and schedule was halted for security reasons.

The semi-finals of rowing, due to take place at the same venue, were also cancelled until Friday.

Poor visibility and a lack of wind meant the latest races in the Finn and Yngling sailing competition were unable to get underway and were set to move to Friday, organisers said.

German shooter Christine Brinker, who collected a bronze in the women's skeet final at the Beijing Shooting Club, claimed the conditions were tough.

"My feet and shoes are very wet," she said after securing third place. "The rain made it very difficult to shoot."

Heavy rain put Olympic tennis quarter-finals on hold with thunderstorms and heavy rain set to bring chaos to tournament.

Top seed Roger Federer was due to face US number one James Blake while Rafael Nadal had an apparently simple task against Austria's Jurgen Melzer.

France's Paul-Henri Mathieu and Gael Monfils were up against Fernando Gonzalez and Novak Djokovic respectively.

In the women's draw, Serena Williams is up against Elena Dementieva and Venus Williams plays Chinese hope Li Na.