Doping scandal hit the Asian Games again when second Uzbek athlete has failed drug tests at the continental sporting event.

Jakhongir Muminov, a Greco-Roman 84kg division wrestler, tested positive for the banned stimulant Methylhexaneamine in an out-of-competition doping test on Nov. 19, Dr. Mani Jegathesan, chairman of Olympic Council of Asia's medical committee, announced in a press conference on Wednesday.

"The athlete has been disqualified from these Games and his performance in the competition has been nullified," said Jegathesan.

In the Games' first doping case, Uzbekistan's judoka Shokir Muminov was stripped of his silver medal last Friday after testing positive for Methylhexaneamine.

"As far as we know, the two athletes are not related," said Jegathesan.

Jegathesan added that there was "no evidence" to prove the systematic use of drgus by Uzbek athletes, though the OCA has asked Uzbekistan to look into the incidents.

"We take each incident separately, but because it involved the same country, and the same substance, in our advice to the NOC concerned, we have indicated to them that it would be worthwhile to investigate and try to find the source of this substance," Jegathesan said.

Uzbekistan delegation officials had reportedly previously blamed contamination from food the athletes had eaten in China for the positive cases.

"These are, obviously, speculations and it is very difficult to prove," said Jegathesan.

Hassan Moheyddine, the deputy head of Uzbekistan delegation, declined to comment when contacted by Xinhua following the OCA announcement.

As of Nov. 23, the organizing committee had conducted a total of 1,262 tests and 1,090 tests have returned the results, according to the OCA medical chief.

According to the WADA Anti-Doping Code, currently, a positive test for Methylhexaneamine carries a two-year ban but it will be re-classified from January, 2011, and thus sanctions for use of the substance can be reduced.

"Any other further sanctioning, such as the ruling of ineligibility for competition, will be according to the rules of international federations as well as the national authorities," said Jegathesan.

Shokir Muminov, 27, lost to South Korea's Kim Jae-Bum by ippon in the 81kg division final, while Japan's Masahiro Takamatsu and Islam Bozbayev of Kazakhstan shared third place.

Takamatsu and Bozbayev were raised to joint second and took silver medals last Saturday.

All samples collected at the Guangzhou Games are being tested at the WADA-accredited lab in Beijing, which conducted drug checks for the 2008 Summer Olympics.

Methylhexaneamine has been the subject of several high-profile doping cases since the WADA added the substance to its banned list this year.

Nigerian sprinter Osayomi Oludamola was stripped of her Commonwealth Games 100 meters gold medal for using Methylhexaneamine. Six Indian wrestlers and three swimmers also tested positive for the same drug ahead of the Games.

The substance is widely used as a nasal decongestant but is also found in recreational drugs. A component of flower oil, the substance is a common ingredient in a variety of nutritional supplements and easily available on the Internet.

Some athletes have said they unwittingly ingested Methylhexaneamine when using supplements or other products.

In last Asian Games in Doha, four weightlifters, including two Uzbekistan athletes, were disqualified for positive doping tests.