Natalie Du Toit opened the Beijing Paralympics on Sunday with a gold medal, which may help her forget a disappointing Beijing Olympics.

Natalie du Toit of South Africa looks at the result board after winning the women's 100m butterfly S9 final during the 2008 Beijing Paralympic Games at the National Aquatics Center in Beijing on September 7, 2008. South Africa's Du Toit, who finished 16th in the Olympics women's 10 kilometres swim, shaved almost half-a-second off her previous mark in the 100m butterfly heats on the first day of competition. [Agencies]

The South African, who won five golds and a silver in the Athens Paralympics, took the 100-meter butterfly in 1 minute, 6.74 seconds.

The time is a world record for Du Toit's disability class.

A swimmer with Olympic promise, Du Toit lost her left leg above the knee in a 2001 motorcycle crash.

She dominated the Paralympics four years ago, and qualified for the Beijing Olympics in the 10-kilometer open water swim.

However, her Olympic race a few weeks ago was a disaster.

Her cap came off as she brushed the buoy on the first turn, and Du Toit struggled the rest of the way with hair in her eyes - stopping at times trying to fix the cap.

She finished 16th.

"It's been a bit of a rough ride from before the Olympics until now," Du Toit said after Sunday's victory.

"It's awesome. Finally I'm swimming a bit faster, which is great."

Du Toit will try for five golds in Beijing.

"Hopefully I'll come back with five," she said.

"But there are going to be one or two races that are tight."

Du Toit said her Olympic training camp was less than ideal, and the 10-K race was about as bad as it could have been.

"I panicked," she said. "I should have stopped and put the cap on properly. For 10 kilometers I stopped three times every lap trying to put my cap on. It wasn't the best race and from lap one I was swearing at myself."

Sixteen gold medals in swimming were up for grabs on Sunday in the Paralympics, with 11 others awarded in shooting, judo and cycling.

The United States won four gold medals in swimming on the opening day, the most of any country.

The winners were: Erin Popovich, Rudy Garcia-Tolson, Miranda Uhl and Jessica Long.

Veronika Vadovicova of Slovakia won the first gold medal of the Paralympics, taking the women's 10-meter air rifle (standing position) early in the day.

Manuela Schmermund of Germany took silver and Nilda Gomez Lopez of Puerto Rico received bronze.

Britain won the first medal in cycling with gold for Simon Richardson in the 1-kilometer time trial.

Masaki Fujita of Japan was second and defending Paralympic champion Greg Ball of Australia was third.

China won two of the four gold medals in judo with victories for Guo Huaping (women's 48 kilo) and Cui Na (women's 52 kilo).