International Space Station Flight Engineer Oleg Kononenko (bottom) is seen outside the PIRS airlock of the Russian segment of the ISS at the beginning of his spacewalk with Commander Sergei Volkov (not pictured) in this image from NASA TV July 10, 2008. The spacewalkers will inspect the Soyuz TMA-12 spacecraft, remove one of the 10 pyrotechnic separation bolts at the interface of two sections of the spacecraft and, if time permits, install a docking target on the Zvezda module for the future arrival of a new Russian module.(Xinhua/Reuters Photo) Photo Gallery>>>

    MOSCOW, July 11 (Xinhua) -- Russian cosmonauts of the International Space Station (ISS) successfully removed an explosive bolt during an unscheduled six-hour spacewalk, the Mission Control Center said Friday.

    The ISS Expedition 17 crew -- Sergei Volkov and Oleg Kononenko -- started the first unscheduled spacewalk at 22:56 Moscow time (1856 GMT) Thursday, and they were supposed to examine Soyuz spacecraft and remove one of its five exploding bolts.

    The main task of the space walk was carried out, Valery Lyndin, spokesman for the Mission Control Center near Moscow, was quoted by the Itar-Tass news agency as saying.

    They took a bolt from the lock that joined the landing vehicle with the apparatus unit of the Soyuz spacecraft, he said.

    A need arose to examine the Soyuz after the spacecraft's dangerously high-speed descent and landing on two recent missions, and as a result, its crew had to endure heavy acceleration forces.