BEIJING - China has planned to investigate an allegation that "99 percent of illegal substances" come from China but remains doubtful of the World Anti-Doping Agency's statistics, a Chinese official said on Tuesday.

China's move came as a result of a striking comment from WADA director general David Howman, who told reporters that "99 percent of the raw materials that are used through the Internet to make up in your kitchen or your backyard laboratory are emanating from China."

Howman's remarks immediately drew great attention from the State General Administration of Sport, the governmental organization that runs sports in China and provides financial support for the country's anti-doping drive.

"We are shocked at Mr. Howman's comment," said China's anti-doping chief Jiang Zhixue.

"We are wondering where this 99 percent came from and what is his evidence," said Jiang. "We have asked for a more detailed explanation from WADA."

Meanwhile, Jiang admitted problems in China's anti-doping fight.

"There are problems, such as illegal sale of banned drugs through the Internet. So we have decided to launch an investigation into WADA's allegation," he said.

Jiang said the probe needs to be coordinated efforts between multiple governmental departments as the action taken ahead of the 2008 Beijing Olympic Games when a number of workshops that illegally produced materials were shut down and supervision and control of drug sales were stepped up.