By ReutersA Russian businessman helping Swiss prosecutors uncover a powerful fraud syndicate has died in unexplained circumstances near his mansion in Britain, in a chilling twist to a Russian mafia scandal that has strained Moscow's ties with the West.
Follow @NBCNewsWorld (http://twitter.com/NBCNewsWorld) Alexander Perepilichny, 44, sought refuge in Britain three years ago and had been helping a Swiss investigation into a Russian money-laundering scheme by providing evidence against corrupt officials, his colleagues and media reports said.
He has also provided evidence against those linked to the 2009 death of anti-corruption lawyer Sergei Magnitsky, a case that caused an international outcry and prompted the United States to push for a bill cracking down on Russian corruption.
NBCNews