Russian investigators accused Sistema's Vladimir Yevtushenkov of money laundering late on Tuesday in connection with his company's acquisition of up-and-coming oil producer Bashneft.
The charges against Yevtushenkov, one of Russia's richest men, raised fears of a return to the bad old days of asset grabs by the Russian state and drew comparisons to the fate of former oil tycoon Mikhail Khodorkovsky who was jailed for a decade.
We've compiled a list of reactions to Yevtushenkov's arrest.
Derk Sauer, Dutch entrepreneur, long time investor in Russian media ventures
Garry Kasparov, former Soviet dissident, chess master, Putin critic
The Khodorkovsky Center, a foundation established to support Putin-era dissident and former-Yukos oil CEO Mikhail Khodorkovsky
Meanwhile, news website Vesti reports former Moscow mayor Yury Luzkhov recommended that Yevtushenkov cooperate with the investigation against him
Alexander Nekrassov, a colorful former-Kremlin adviser and Voice of Russia columnist