Billionnaire Chelsea football tycoon Roman Abramovich has sold his stake in Russia's biggest aluminium firm, according to Russian press reports.
Roman Abramovich is thought to be the second richest man in Russia
The sale will fuel rumours that the 36-year-old is transferring his assets out of Russia, amid a spate of arrests of the country's business elite.
In March, Mr Abramovich sold off his 26% share in the national airline Aeroflot.
He is also a chief sharehold in Sibneft, the oil company merging with Russia's largest oil producer Yukos, to form
the world's fourth-largest private oil
Mr Abramovich denies he is turning his back on Russia but has said more of his assets in the country may be up for grabs.
His 50% stake in Russian Aluminium has been sold to Basic Element, which owns the other half of the company, according to the Vedemosti newspaper.
Mr Abramovich's Millhouse Capital investment house has so far declined to comment on the deal.
But commentators in Russia say the selling of assets by its oligarchs is a bad sign.
Mr Abramovich made a killing out of the crash privatisation programme that followed the collapse of Communism
"Abramovich is one of the most well-informed and well-protected people in this country.
"If he is rolling up his activities in Russia, where he became one of the richest people in the world, it means that he has good reasons for
this," Moscow magazine Yezhenedelnyy Zhurnal editor-in-chief
Mikhail Berger told Ekho Moskvy radio.
In July, Mr Abramovich, who is governor of Chukotka, in Russia's far east, stunned English football by buying leading club Chelsea for £140m.
He has since spent a further £100m on signing top players.
But he has denied the purchase of the club - and the sale of his stake in the aluminium firm - are part of a strategy of transferring assets out of his home country.
"We are selling some things and buying other things. I don't feel like doing business outside Russia," Mr Abramovich said through a spokesman.
Mr Abramovich may be distancing himself from Russia, as arrests of leading business people continue, according to press reports.
Platon Lebedev, a key business ally
of the country's richest man Mikhail Khodorkovsky, was arrested in July and charged with theft of state
Media tycoon Vladimir Gusinsky has been arrested in Greece on multi-million-dollar Russian fraud charges.
Russian billionaire Boris Berezovsky was arrested in the UK in April, after Moscow requested his extradition on fraud charges which have since been thrown out of court by a London judge.
But the moving of assets abroad by oligarchs pose a threat to
Russia's national security, the head of the parliament's committee for foreign debt and foreign assets has warned.
"If revenues, including those received in the raw materials
industry, go abroad, economic growth and investment activity
will become impossible in Russia," Vladimir Nikitin told Ekho Moskvy radio.
"Having gained huge financial resources from society virtually for a
song, the economic elite has proved to be totally incapable of acting as efficient owners."