Russia has arrested two suspects believed to be behind the assassination of a senior naval officer who was killed by a car bomb in Crimea last week, investigators said on Tuesday. Valery Trankovsky, a naval captain and the chief of staff of the 41st brigade of Russia's missile ships in the Black Sea, died in a black saloon car that was blown up in the city of Sevastopol. A source in the Security Service of Ukraine (SBU) told Reuters at the time that it was responsible for the operation, describing Trankovsky as one of the most senior Russian officials that Kyiv has targeted in this way.