Russia's space agency denied Saturday that an astronaut could have flown drunk aboard a Soyuz spacecraft from its Baikonur cosmodrome, reacting to allegations reported by the chairman of an independent U.S. panel on astronaut health.

The panel chairman, Air Force Col. Richard Bachmann Jr., said Friday it was told about multiple instances involving alcohol. One of the two most detailed cases involved an astronaut drinking heavily before flying on a Soyuz spacecraft headed to the International Space Station, he said. He cited unverified interviews, saying it was not the panel's mission to investigate the allegations.

"We categorically deny the possibility that this could have happened at Baikonur," Igor Panarin, spokesman for the Russian Space Agency, Roskosmos, told The Associated Press. "In the days at Baikonur before the launch, this is absolutely impossible. They are constantly watched by medics and psychiatrists."

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The U.S. panel was created to assess NASA's health screening in response to the high-profile arrest of astronaut Lisa Nowak in February after she drove across the country to confront a romantic rival.

Russian cosmonaut Anatoly Solovyov told the AP that the tight medical requirements and the demands of the job ahead made it inconceivable that either astronauts or cosmonauts could fly drunk.

"They are the elite of their society," said Solovyov. "The responsibility dominates your thoughts. In your head, you know this is a state program and this dominates your mind and directs all your actions. For me this is nonsense."

Despite official denials of drinking before Russian flights to the space station, cosmonauts aboard the Mir space station, which has since been abandoned, were permitted to imbibe moderately. Cosmonaut Alexander Poleshchuk, who flew aboard the Mir space station in 1993, told newspapers of removing panels to hunt for bottles of cognac squirreled away by previous tenants.

Alcohol consumption is forbidden aboard the International Space Station, which has caused some mild grumbling. Cosmonaut Salizhan Sharipov returned from an ISS mission in April 2005, and caused a stir when he said the crew should be allowed a shot of wine or brandy daily.

"This should be done only to do one's work better and relieve the psychological stress," he said, according to the Russian wire service RIA Novosti.

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