Beijing - Christine Ohuruogu of Britain won the 400 metres Olympic gold medal on Tuesday, nine months after an arbitration panel allowed her to compete in Beijing.

Dawn Harper won 100m hurdles gold after leading favourite and fellow-American Lolo Jones clipped the penultimate hurdle and the 2005 world champion Rashid Ramzi won the first ever athletics gold for Bahrain, in the 1,500m. European champion Andrei Silnov of Russia claimed high-jump gold, Estonian Gerd Kanter raced down the home stretch in delight after his first discus gold and the eternal jogger Usain Bolt danced into the 200 metres final.

Away from the Bird's Nest, China continued to dominate gymnastics and Britain the cycling, while Argentina thrashed Brazil in the semi- finals of the football and there were especially emotional victories for US wrestler Henry Cejudo and German weightlifter Matthias Steiner.

On the track Ohuruogu, 24, stormed past long-time leader Sanya Richards of the US to take 400m gold in 49.62 seconds, with Jamaica's Shericka Williams stealing silver and Richards having to settle for bronze.

Ohuruogu had to serve a one-year ban for missed doping tests 2006/2007. Under British rules doping offenders are banned from future Olympics, but Ohuruogu successfully appealed last November.

Harper was an unexpected hurdles winner as Jones suffered the same fate as Gail Devers in the 1992 final. While Devers clipped the 10th and final hurdle in Barcelona that year Jones' fate was sealed one hurdle earlier and she faded to seventh.

Harper won in a personal best 12.54 seconds and Sally McLellan of Australia won silver in a photo-finish against bronze Priscilla Lopes-Schliep of Canada, with both on 12.64 seconds. Only two hundredths separated second from sixth place.

The 2008 world leader Silnov cruised to his biggest career victory by clearing all heights up to the winning 2.36 metres on his first attempt. He then missed three times on a Russian record 2.42m, which is four centimetres higher than his personal best 2.38m.

In the 1,500m Ramzi was unbeatable on the home stretch to win in 3:32.94 minutes. Kenya's Asbel Kipruto Kiprop took silver with 3:33.11 and a strong finish gave New Zealand's Nicolas Willis bronze in 3:34.16.

Kanter won discus gold with 68.82m. While sprint sensation Bolt continued his jogging training in the Birds Nest with a 20.09 run for a place in Wednesday's 200m final.

Away from the track China and Britain continued their domination of gymnastics and cycling respectively.

In the National Indoor Stadium Lu Chunlong won the men's Gymnastics Artistic Trampoline, Zou Kai won the men's artistic parallel bars and Li Xiaopeng, winning his second gold of the Games, took the men's Artistic Parallel Bars.

Only US gymnast Shawn Johnson could break the Chinese dominance winning the women's Artistic Beam to finally earn a gold after picking up four silver medals.

China also took gold in diving with He Chong winning the men's 3m springboard.

In cycling, Britain made it seven out of a possible 10 track golds with Chris Hoy and Victoria Pendleton winning the men's and women's sprints. Hoy's gold made him the first Briton since swimmer Henry Taylor 100 years ago to win three golds in one Games.

And it capped another impressive day for Britain with Paul Goodison claiming their third Olympic sailing gold in the men's Laser category.

Britain is now battling with Germany for European bragging rights in the medals table. German triathlete Jan Frodeno won his country's first gold of day 11 and was followed by Steiner in the men's 105kg weightlifting division.

In an emotional medals ceremony Steiner held a picture of his deceased wife Susann as he was presented with the Olympic gold.

Steiner, who was born in Austria and competed for them in Athens four years ago, applied for German citizenship after marrying his wife Susann in December 2005.

She died in a car accident in July last year - a few months before he was given German citizenship.

Steiner claimed a dramatic victory lifting 258kg on his last attempt in the clean and jerk, for a total of 461kg to beat Russian Evgeny Chigishev by 1kg.

At the medal ceremony, he held a photograph of his wife in his hands, kissed it before receiving his medal and then placed it on the podium as the national anthem was played.

Another emotional gold medal winner was US wrestler Cejudo, who stunned the favourites in the freestyle 55kg class when he beat Japan's Tomohiro Matsunaga in the final.

The 20-year-old son of illegal immigrants sunk to his knees draped in the US flag after his victory. He was the youngest member of the US team and not considered a favourite for gold.

In the biggest non-medal event of the day Argentina met Brazil in the Olympic football semi-final.

Billed as the battle between Leo Messi and Ronaldinho, it was a Messi-inspired Argentina that came out on top. Atletico Madrid's Sergio Aguero scored twice and Brazil had Lucas and Neves sent-off as Argentina won 3-0. In Saturday's final they will face Nigeria, who easily overcame Belgium 4-1.