A Russian general was killed Monday morning after an explosive device detonated underneath his car in Moscow, and investigators said Ukraine could be behind the attack, the third such killing of a senior military officer in a year.

Lt. Gen. Fanil Sarvarov, head of the Operational Training Directorate of the Russian Armed Forces' General Staff, died from his injuries, said Svetlana Petrenko, the spokesperson for Russia's Investigative Committee, the nation's top criminal investigation agency.