Aleksei Burkov, a cybercriminal who long operated two of Russia’s most exclusive underground hacking forums, was arrested in 2015 by Israeli authorities. The Russian government fought Burkov’s extradition to the U.S. for four years — even arresting and jailing an Israeli woman to force a prisoner swap. That effort failed: Burkov was sent to America, pleaded guilty, and was sentenced to nine years in prison. But a little more than a year later, he was quietly released and deported back to Russia. Now some Republican lawmakers are asking why a Russian hacker once described as “an asset of supreme importance” was allowed to shorten his stay. …

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