LONDON—For many of the thousands of Russians who have helped lend this city the nickname Moscow-on-Thames, the nerve-agent poisoning of one of their countrymen is a jarring intrusion from a world they thought they’d left behind.
They have little in common with the older waves of emigres who have earned the ire of the Kremlin, the wealthy oligarchs lured in part by a controversial investor program, or the likes of Sergei Skripal, the 66-year-old Russian double agent now fighting for his life.
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