Russia intends to step up security for high-ranking military officials, the state-run TASS news agency reported on Thursday, citing Federal Security Service (FSB) chief Alexander Bortnikov.For all the latest headlines follow our Google News channel online or via the app. A string of Russian military figures and high-profile supporters of the war in Ukraine have been assassinated during the nearly four-year-old conflict. Ukrainian military intelligence has said it was responsible for a number of the attacks.Read more:Russia calls for ‘safety island’ around Iran’s Bushehr nuclear plant