The Foreign Office has blamed the Russian state for the death of opposition leader Alexei Navalny, which it said was the result of poisoning from a dart frog toxin ....
Russian opposition leader Alexei Navalny died in prison after being poisoned with a deadly toxin found in Ecuadorian dart frogs, the U.K. and other allies claimed Saturday ... .
Five European foreign ministers say analysis of samples from the former Russian opposition leader, who died two years ago, confirmed the presence of a toxin from poison frogs ... .