Volodymyr Tsemakh, whom Ukraine's security service has identified as a former commander of Russian-backed separatist forces in eastern Ukraine, was transferred to Russia in an exchange of prisoners between Moscow and Kiev, the Dutch Foreign ministry said.
Dutch prosecutors had urged Kiev not to allow Tsemakh to travel to Russia, fearing this could jeopardize the investigation into Flight MH17. He was released on bail by a Ukrainian court on Thursday.