An explosive device planted near an apartment building in Moscow killed the head of Russia’s nuclear and chemical forces early Tuesday, officials said. Russia’s Investigative Committee said the bomb, which was triggered by the device placed in a scooter, killed Lt. General Igor Kirillov and his assistant. Kirillov, who was named the head of Russia’s nuclear defense forces in April 2017, was under sanctions from several countries including the U.K. and Canada for his role in Ukraine.