MOSCOW, 28 November - RAPSI. Police informant and key witness in the Magnitsky case Alexander Perepilichnyy has been found dead in his Surrey mansion, The Independent [UK] reported Tuesday, adding that the healthy 44-year-old is the fourth person linked to the Magnitsky scandal to have died suddenly.

According to the report, Perepilichnyy had provided key evidence against the "Klyuev Group," described as "an opaque network of corrupt Russian officials and underworld figures implicated in a series of multi-million pound tax frauds," as well as Magnitsky's death.

Investigations into the cause of Perepilichnyy’s death have proved inconclusive thus far, but remain ongoing.

Hermitage Capital counselor Sergei Magnitsky accused law enforcement officials in 2008 of a $230 million tax fraud.

Shortly after coming forward with these accusations, Magnitsky was arrested on charges of having masterminded large-scale corporate tax evasion. According to investigators, Magnitsky and his accomplices stole hundreds of millions of rubles from the state by manipulating tax returns between September and October 2007.

The attorney died in a Moscow pretrial detention center on November 16, 2009 after spending a year behind bars. According to the Prosecutor Generals Office, his death was caused by cardiovascular insufficiency. Magnitsky's death sparked a public outcry and triggered amendments to the Criminal Code and a reshuffling of officials in the penal system.

This outcry proved powerful enough to traverse the Atlantic Ocean. Earlier this month, an overwhelming majority of US House representatives voted in favor of passing the Magnitsky Act, which punishes Russian individuals thought to have violated human rights by depriving them of the rights to enter the US or maintain property and other assets in the country.