Two crew members of the International Space Station (ISS), have successfully completed their spacewalk, the Interfax news agency reported on Wednesday.

Leroy Chiao, the American commander, and Salizhan Sharipov, a Russian, entered the station and closed the hatches of the Pirs docking compartment at 4:11 p.m. Moscow time (0111GMT) Wednesday.

They worked in space for five and a half hours, installing a multipurpose working platform, a European-made manipulator and other scientific equipment. They also checked the vents and took pictures of them.

The two men also installed outside the station three containers with mushrooms and bacilli and fulfilled other operations over period of work on the space.

During the spacewalk, flight controllers noticed a repeat of the same mysterious forces that tilted the station on previous astronaut outings. Wednesday's odd, off-center nudges forced the Russian thrusters to temporarily take over steering control from the US gyroscopes several times.

It is the first for the tenth main mission crew working in orbit since mid-October. Sharipov and Chiao never worked wearing Russian spacesuits Orlan-M in the open space, according to the report.

One more spacewalk is scheduled for Chiao and Sharipov in March, one month before they return to Earth in a Russian capsule.