Defects in the control system were to blame for the failure to launch a South Korean rocket on Thursday, spokesman for Russian company Energomash told the Interfax news agency Friday.

The company built the first stage of the Korea Space Launch Vehicle-1 (KSLV-1) rocket, also called naro-1 rocket, which functioned as planned, according to the spokesman.

"What happened was not our fault. We did everything right. The Russian-made engine functioned as planned," he said, adding that no reports on any problems linked with its operations were made.

The South Korean rocket carrying a scientific satellite failed to reach orbit and apparently exploded a few minutes after the blastoff on Thursday.

The explosion was reported to have occurred during its first-stage ignition.

This was South Korea's second launch failure after another naro-1 rocket failed to enter orbit after a launch on Aug. 25, 2009.

Moscow-based Khrunichev space research center said the same day that Russia and South Korea would establish a joint commission to investigate the cause of the flop.