A Moscow court on Friday sentenced anti-Kremlin campaigner William Browder in absentia to nine years in a penal colony after convicting him of deliberate bankruptcy.

The US-born British citizen has led a campaign in memory of his former employee Sergei Magnitsky, who went public with details of massive fraud by Russian state officials before dying in detention after spending 11 months in squalid prisons in 2009.

"Browder is found guilty and is sentenced to nine years in a general security penal colony," the Moscow judge said.

The court also ordered Browder, the head hedge fund manager at Hermitage Capital Management, and his Russian partner Ivan Cherkasov to pay a total of 4.2 billion rubles ($72 million, 60 million euros).

The Russian prosecutor general's office said on Friday that it will continue to ask Interpol for the extradition of Browder, who is based in London."The prosecutor general's office did not stop and is not stopping to seek Browder's extradition to Russia," prosecutor Mikhail Reznichenko said, as quoted by Russian news agencies.

In 2012, the US passed the "Sergei Magnitsky Act" which imposed a visa ban and froze the assets of Russian officials implicated in the lawyer's death. The act became a symbol of prison abuses in Russia and strained ties with Washington.

In retaliation, Moscow passed legislation prohibiting Americans from adopting Russian children.

In a statement sent to AFP, Browder dismissed the sentence as a sign of Russian President Vladimir Putin's "desperation about the global wave of Magnitsky sanctions.

"Putin has been unable to stop the Magnitsky legislation so now he's doing everything possible to try to stop me from advocating in new countries."

A Moscow court had already sentenced Browder in absentia to nine years prison for tax evasion in 2013.

A Russian court also convicted Magnitsky of tax evasion in 2013 -- despite his death four years earlier -- in an almost unprecedented trial of a dead person in post-Soviet Russia.