Updated

A Russian defense company worker was convicted Friday of passing missile secrets to foreign intelligence in the latest espionage case amid a cold spell in Moscow's relations with Washington.

The Sverdlov Regional Court in the city of Yekaterinburg handed an eight-year prison sentence to Alexander Gniteyev, a worker at a defense company dealing with automatic systems. Court spokesman Yelena Maryina said Gniteyev also has been ordered to pay a 100,000 ruble ($3,200) fine.

Anna Lastovitskaya, a spokeswoman for the regional branch of the Russian Federal Security Service, the top KGB successor agency, said Gniteyev had divulged missile secrets to foreign intelligence, but wouldn't say what country Gniteyev was spying for.

Russian news agencies said that Gniteyev had handed over secrets related to the Bulava missile, developed to arm the latest generation of Russian nuclear submarines.

Military officials have repeatedly boasted of the Bulava's ability to penetrate any prospective missile defenses and described it as the core of the nation's nuclear deterrent for years to come. The Bulava suffered a string of failures during its development, but the latest launches have been fine and officials say it will be commissioned later this year.

The court verdict follows February's conviction of a Russian military officer accused of providing the CIA with secret information on new missiles. U.S.-Russian relations have also soured over U.S.-led NATO missile defense plans for Europe, which Russia sees as a potential threat to its nuclear forces.

Vladimir Putin frequently lashed out at the U.S. during his campaign for a third presidential term, which he won in March, accusing Washington of driving the mass protests against his rule in an effort to weaken Russia. He has snubbed the Group of Eight Summit in Chicago this weekend, saying he is too busy forming his new Cabinet. Prime Minister Dmitry Medvedev will represent Russia at the summit.