World leaders on Friday reacted with dismay and suspicion to reports of the death of prominent Russian opposition leader Alexei Navalny in a Siberian penal colony. Russian media reported, citing the prison service of the Yamalo-Nenets region where Navalny had been serving a lengthy sentence on what were widely considered to be politically motivated charges, that he had fallen ill and collapsed after a walk. Navalny's team said they had yet to receive confirmation of the death and questioned the veracity of the announcement. U.S. Vice President Kamala Harris told the Munich Security Conference on Friday that Washington was working to confirm the "terrible" news. "Whatever story they tell, let u