Earlier this month, the U.S. House of Representatives approved a measure that imposes visa and financial restrictions on Russian officials linked to human rights abuses. Browder, who has pressed for such restrictions, plans to push for similar measures in Canada next week.
Many Russians who have fled to the U.K. for various reasons have reported being targeted.
In March, a former Russian banker was shot in an apparent assassination attempt in east London after giving evidence in a 2009 attempted murder case. German Gorbuntsov suffered several gunshot wounds outside an apartment block close to London's Canary Wharf financial district. Scotland Yard is still investigating the shooting.
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