CHINA'S World  No 1 Yi Siling won the  first gold of the London Olympics in the women's 10m air rifle competition at  London's Royal Artillery Barracks  yesterday.

In a tense contest watched by International Olympic Committee president Jacques Rogge, Poland's Sylwia Bogacka took silver after a fierce battle for the top spot while Yu Dan of China clinched bronze.

Siling, 23, who won the title at the 2010 world championships in Munich, had a total winning score of 502.9, 0.7 points ahead of Sylwia, on 502.2. Yu Dan finished with 501.5.

Defending Olympic champion Katerina Emmons of the Czech Republic finished fourth.

Siling, who was well off her own world record of 505.6, said it felt good to be the first gold medal winner of the 2012 Games.

"It's very exciting. Very happy. I'm very grateful to China. And to my mother and father who I love very much," she said. "I am pleased, not nervous like I was in the competition. I have been up since five this morning. There was a lot of pressure on me."

And Siling said being Olympic champion would change her life.

"I think I myself have changed. I feel like I've grown up and then I think this is going to bring some changes to my life as well."

Sylwia earlier finished top of qualifying with Siling in second place and the two were locked together in an agonisingly tight duel in the final which started with both scoring 10.8 out of possible 10.9 in the first shot.

But Siling held her nerve under intense pressure, taking advantage of some slips from the Pole, grabbing the title with 10.3 and 10.5 in her last two shots.

Sylwia slipped to third after the ninth shot but her final effort (10.8) lifted her into the silver medal position.

"Amazing, really, really amazing. The people were amazing. I'm very happy," said the Pole, 30. "I have been shooting for 18 years. This is everything to me."

When asked where she felt she lost the gold medal, she said: "I shot one 9.7, I think that was the reason I fell down."

South Korean sharpshooter Jin Jong-Oh won Olympic men's 10m air pistol gold while Italy's Luca Tesconi made a brave attempt to close a seemingly impregnable gap to Jong-Oh at one stage in the final to secure silver, 2.4 points behind the winner, while Serbia's Andrija Zlatic won bronze. AFP