A Kenyan acrobat has fallen through a safety net during a show at a Moscow circus, suffering severe injuries including a fractured vertebra.

An amateur video aired on Russian television showed 22-year-old Karo Christopher Kazungu diving from a height of 26 meters (85 feet), hitting the net and going through it and landing on the arena floor during the show.

Kazungu was at the end of his routine and was due to dismount after the dive.

Edgard Zapashny, director general of the Great Moscow State Circus, told Russian television that the German-made safety net had been rigorously tested before it was used.

Circus employees are speculating on whether someone may have tampered with the net or whether it was faulty. Zapashny said, however, that they did not see any signs of sabotage on first inspection.

The circus said on its website that Kazungu was conscious when he was taken to the hospital.

Russian news agencies quoted the director of the acrobatics show as saying that Kazungu was diagnosed with a fracture of one vertebra and was in intensive care.

Kazungu was one of a dozen Russian and Kenyan performers taking part in a highly complex acrobatics show.

Zapashny told Russian television that the circus had never had any previous incidents of this kind.

- AP