Navalny Poisoned with Rare Frog Toxin, Suggesting Human Experiment

European investigators have identified the poison that killed Russian opposition leader Alexei Navalny. The substance is epibatidine, an extremely lethal toxin from South American poison dart frogs. Navalny died in a Russian prison two years ago. The new finding raises a disturbing question: why use such a rare, exotic poison? Some security experts suggest the motive may have been testing. They believe Navalny could have been used as a "lab rat" to trial the obscure toxin. This would make the poisoning both an assassination and a potential experiment. Epibatidine is not a typical weapon. It is naturally found only in frogs in Ecuador and Colombia. Using it requires specialized knowledge and access. The investigation was led by five European countries. They have not publicly detailed how they obtained their evidence. Russian authorities have consistently denied involvement in Navalny's death.