China's Anti-Doping Agency says there has been no "cover up" of positive doping tests by the country's swimmers and that the results of its investigations will be released in line with regulations, the official Xinhua news agency has reported.
The article, published late on Thursday, comes after The Times newspaper in London reported claims by whistle-blowers that five positive tests, two believed to have been failed in October and the others at the turn of the year, were suppressed "to avoid a storm".
Xinhua quoted the deputy director of the Chinese anti-doping agency (CHINADA), Zhao Jian, as saying there was no "cover-up" and that it was following regulations.
The agency had yet to disclose athletes' information because of the time needed to test B samples and to conduct an investigation and hearings, prior to which the relevant information had to be protected, he said.
CHINADA would "release results and punishments in 20 days after the relevant association makes its respective punishments", Zhao said.
The World Anti-Doping Agency said on Thursday it was investigating allegations published by The Times that Chinese Swimming had covered up positive doping tests ahead of the Olympic trials, which are due to be held in April.
WADA issued a statement soon after, stating "these are very serious allegations concerning Chinese Swimming that warrant further examination".
The agency is now fully scrutinizing the information so it can determine exactly what the appropriate steps are, it said.
The Chinese Swimming Association announced previously that six Chinese swimmers had failed doping tests during the 2015-16 season. It identified three of them as Chinese Navy's Zhao Ying, Wang Lizhuo and Tianjin's An Jiabao, who tested positive for Clenbuterol in out-of-competition tests.
The other three, who tested positive for the prohibited diuretic hydrochlorothiazide in out-of-competition tests in January and who have applied for hearings since, were not named.
Officials reached by telephone at the association declined to comment on The Times article, or the doping issue in general.
A second Chinese-language Xinhua article cited a 2015-16 doping report published by the association on Thursday as saying that the athletes' information needed to be protected before CHINADA completed its procedures.
A copy of the CSA report could not be found online by Reuters on Thursday.
China, which has been seeking to elevate its sports prestige on a global scale, views swimming as an important part of that national effort.
At the 2012 London Olympics, China finished second to the United States in the swimming medal table, but topped the table at the World Aquatics Championships in Kazan, Russia.