Russia’s top investigative agency has filed criminal charges against tycoon and UK newspaper backer Alexander Lebedev.
The State Investigative Committee said it had charged Mr Lebedev with hooliganism and assault over a TV show incident in which he punched another businessman.
Mr Lebedev, whose net worth was reported by Forbes magazine to be $1.1bn, made his money in the banking industry and owns a stake in Russian flag carrier Aeroflot as well as his own Red Wings airline.
He has financed Novaya Gazeta, which is fiercely critical of the Kremlin, as well as the UK’s Independent, Independent on Sunday, i newspaper and the Evening Standard.
His son Evgeny, owner of the UK newspapers said: “This is an extraordinarily disproportionate response to what happened in a TV studio many months ago.
“My father has been targeted because of his determination to fight against corruption and to be a crusader for democracy in a country where this has not always been welcome.
“My father has spent his life trying to promote freedom of expression and justice in his fight against corruption in Russia.
“I hope that common sense prevails and that these excessive charges are dropped.
“I really hope that this does not presage a new phase of crackdowns on those who speak out against injustice.”
Mr Lebedev senior said Russia’s Federal Security Service, the main KGB successor agency was putting him under pressure because of investigations by Novaya Gazeta, alleging some of its officers were involved in corruption.
He and former Soviet leader Mikhail Gorbachev own a 49 per cent stake in the newspaper, while the remaining shares are controlled by Novaya’s staff.
Novaya Gazeta’s relentless criticism of the Kremlin, and its investigations into official corruption have put many of its journalists under fire.
Four Novaya Gazeta reporters have been killed since 2000, including Anna Politkovskaya, a fierce critic of the Kremlin and its policies in Chechnya who was gunned down in the lift of her Moscow apartment building in 2006.
Others have been harassed and attacked.
Mr Lebedev has also supported Alexei Navalny, a charismatic anti-corruption crusader and blogger who was a key driving force against massive protests in the past winter against Vladimir Putin’s rule.
A KGB veteran like Mr Putin, Mr Lebedev so far has avoided blaming the president for his woes, blaming security services for the campaign against him.