The FSB in the Siberian town of Krasnoyarsk said scientist Valentin Danilov was arrested and charged with treason for trying to sell information on the effects of space on satellites.
Danilov, head of the Thermo-Physics Center of Krasnoyarsk State Technical University, is the latest scientist to fall foul of the FSB, a successor to the Soviet-era KGB, in a spate of spy scandals that has hit Russia.
Colleagues, who have written an open letter to local prosecutors demanding that Danilov be released from detention, said he was arrested in connection with work carried out under contract for a Chinese research center.
One fellow researcher said Danilov's work dealt with the effects of solar activity on satellites, which the FSB might see as sensitive due to its relation to the development of anti-satellite weapons.
"This is Star Wars stuff...But anyone with experience in the field could have put together what he was doing," said the man, who declined to be named for fear of implication in the case.
But FSB spokeswoman Stella Alekseyeva said by telephone from Krasnoyarsk that investigators had clear grounds for the arrest.
"Damage has been done to Russia's external security," she said. "Danilov's actions have allowed foreign countries to significantly cut the amount of time (and) money spent on the development and creation of space craft."
Danilov's fellow workers said his research had been secret until 1992, but its security status was then lifted.
"There is really nothing at all secret about the work. Virtually all his research has long been in the public domain," the colleague said. "A mistake is being made here."
He said Danilov was arrested on February 16 but was first detained and questioned for three days last May.
Danilov's lawyer, Yelena Yevmenova, said she had expert testimony that her client had revealed no state secrets.
She said Danilov "felt as well as can be expected for a man in prison" but that she hoped to see him granted bail in the case, which was unlikely to go to court before September.
"Within two weeks I hope to be able to again ask (for bail)...It is even possible that we could see this case dismissed altogether," she said.
His colleagues demanded any trial be held in public and not behind closed doors as is usually the case in secrets trials.
Some of Russia's recent spy scandals have involved scientists working with foreigners. One involved U.S. businessman Edmond Pope, who was sentenced to 20 years for allegedly stealing secrets of an underwater missile but later pardoned by President Vladimir Putin and freed.
Igor Sutyagin, an arms expert at Russia's respected USA-Canada Institute, is still on trial on charges of passing secrets about Russian nuclear submarines to the United States and Britain.
Suyagin was arrested by the FSB in October 1999 and faces up to 20 years in prison if found guilty. He denies the charges.
The FSB has said the Sutyagin case should serve as a warning to other researchers to consider carefully any work they do for foreign firms.
Military researchers in Russia say they run a daily risk of being accused of espionage because the guidelines regulating their work are so vague.
By Yelena Smirnova
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