An autopsy of exiled one time mogul Boris Berezovsky in London...revealed that he died by hanging.
He was found on the floor of his bathroom in an exclusive London suburb.
More tests...including toxicology...will take several weeks.
Berezovsky, 67...was a close Yeltsin...and then Putin ally in the 1990's...but won asylum in the UK in 2003...after he fell out of favor...and was later convicted in absentia in Moscow of embezzlement.
He was Russian President Putin's biggest critic.
There were reports he was suffering from depression after losing a $4.7 billion lawsuit over the sale of his shares in Russian oil company...Sibneft...and was under financial pressure.
He was forced to pay his ex-wife a $153 million settlement...and $53 million in court costs after suing a former Sibneft partner.
He had befriended Alexander Litvinenko...a former Russian spy...who died mysteriously in London...from slow and painful radiation poisoning.