Chinese anti-doping officials pledged on Thursday to enforce a transparent and open doping control system to combat doping cheats and host clean Olympic Games.

"We will catch those drug-users and make sure they get penalized as they should be," said Chen Zhiyu, anti-doping division chief of Beijing Games organizing committee.

Beijing plans to conduct 4,500 Olympic doping tests, about 25 percent rise from the Athens Games, which witnessed 26 doping cases.

A total of 917 staff will work at 34 doping control stations to collect samples, which will be tested at a lab for about 200 banned substances, Chen said.

At the Beijing Olympics, enhanced tests will be carried out for erythropoietin (EPO), a protein hormone which raises oxygen-rich red blood cells, and human growth hormone (HGH), a substance that boosts strength and speeds recovery. Both are choice performance-enhancers.

"You shall see from the number and types of tests our resolution to host a clean Games. Those who risk using drugs will be filtered out by a clean system," said Dai Jianping, a Games service deputy chief.

A new test kit can track the use of HGH beyond 48 hours, and the EPO tests are also reliable, said Wu Moutian, deputy director of the Chinese Anti-doping Agency, who oversees the lab.

Battle between drug-users and testers has been perennial, and will be more intense at the Beijing Games.

International Olympic Committee President Jacques Rogge predicted that as many as 40 Olympians could test positive for banned substances in Beijing.

Wu declined to make any prediction, and said the results could only be available after all the tests are completed. "My task is to carry out the tests in accordance with international standards. We will catch the cheater when there is one," he said.