Hermitage Capital Management, the London-headquartered hedge fund which invests in Russia and the CIS region, is under attack from the Russian Interior Ministry, as the government organisation seeks the arrest of Ivan Cherkasov, a senior executive of Hermitage Capital.

The firm’s lawyers received a decree signed by Major Oleg Silchenko of the Russian Federal Interior Ministry seeking the arrest in absentia of Cherkasov, Hermitage Capital said in a statement.

Major Silchenko is the same Interior Ministry officer who was responsible for the investigation and 12-month detention without trial of anti-corruption lawyer Sergei Magnitsky, the firm said. Magnitsky was detained by Silchenko, after Magnitsky testified that Interior Ministry officers were allegedly involved in the theft of $230 million from the Russian government. In November last year Magnitsky died in custody after being denied medical treatment for the conditions he developed in detention.

Earlier this year, lawyers representing Hermitage Capital and Cherkasov wrote complaints to both the Russian General Prosecutor office and Federal Tax Service.  The complaints exposed the involvement of officers of the Silchenko’s team, in the theft of 11.2 billion rubles ($500 million) from the Russian government. They also accused investigators of fabricating evidence in order to raid Hermitage’s offices and arrest and detain Magnitsky.

In early March this year, a month after receipt of the complaints, Major Silchenko issued a decree seeking the arrest of Ivan Cherkasov.

“The officers responsible for Sergei’s death are now trying to find another hostage,” said a spokesman for Hermitage Capital.

The criminal case being brought against Cherkasov by the Russian Interior Ministry for alleged underpayment of dividend withholding taxes at Kameya, a Russian investment company advised by Hermitage, is in direct contradiction to the multiple audits conducted by the Russian Federal Tax Service, which found Kameya’s tax affairs to be completely in order and that no taxes were owed but had in fact been overpaid.

Also, William Browder, the founder of Hermitage Capital, has been banned from entry to Russia for over four years as part of a campaign brought by Russian officials against the fund.