Russian airspace control systems detected an air target approaching the state border over neutral waters.
"To identify the air target and prevent violation of the state border of Russia, a Su-27 fighter was raised into the air, the crew of which classified it as a strategic reconnaissance aircraft RC-135 of the US Air Force and escorted it over the Black Sea," RIA Novosti quotes the defense department.
On September 4, eight Russian fighters flew to intercept three US Air Force B-52H strategic bombers, which were approaching the Russian state border.