Russian prosecutors released a statement naming two of the attackers as young Chechen men, aged 22 and 21.

Instead, the defense had to prove its existence through numerous affidavits that were subject to continued objections on the part of the Russian prosecutors.

Gazprom said it would ask the Russian prosecutor general to investigate.

On 27 December 2005 Russian prosecutors dropped these charges.

Russian prosecutors were not allowed to investigate the office.

However, this was later refuted by the Russian prosecutors.

The Russian prosecutor told the tribunal that he was sure of it.

On 23 May 2012, Russian prosecutors for the first time publicly disclosed details about the case.

"Some of my accounts are frozen in Switzerland, initiated by Russian prosecutors," he said.

Russian prosecutors are investigating the episode, which became an international embarrassment.