WASHINGTON - Multiple Russian military aircraft came close to a US Navy destroyer in the Black Sea on Feb. 10, incidents considered to be 'unsafe and unprofessional,' a US official said on Tuesday. Captain Danny Hernandez, a spokesman for US European Command, said there were three separate incidents involving Russian aircraft and the USS Porter. One involved two Russian SU-24 jets, another involved a separate SU-24, and the third involved a larger IL-38. 'USS Porter queried all aircraft and received no response,' Hernandez said. 'Such incidents are concerning because they can result in accident or miscalculation,' he added