The British government says Russia poisoned an ex-spy in the UK. Now London is striking back

UK Prime Minister Theresa May said her country will expel 23 Russian diplomats on Wednesday — which would be the country’s largest removal of foreign officials in more than 30 years.

Here’s why: On March 4, Sergei Skripal, a former Soviet and Russian spy, was found unconscious on a bench alongside his daughter Yulia. According to May, they were poisoned with a nerve agent known as “Novichok” in Salisbury, Southern England, where he lives. Both Skripal and his daughter are still in the hospital and are reportedly in dire condition.

Novichok is part of a group of nerve agents considered to be the most lethal in the world, and the Russian government has been producing it for decades.

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