Authorities search TNK-BP's Moscow office

Shares in Russo-British oil major TNK-BP have plummeted 10 per cent following the news that the company's head office is being searched by the Russian authorities.

Interfax is reporting that the officers who entered the building are from the Interior Ministry and are seizing documents as part of a criminal case against the Sidanko oil company.

TNK-BP has confirmed to Russia Today that a search is underway, but would not comment on the nature of the investigation.

The Federal Tax Service accuses TNK-BP of tax evasion. A case was launched after the company conceded the Kovykta gas field to the Russian gas monopoly Gazprom.