MOSCOW, April 23. /TASS/. An American Bombardier Challenger 650 Artemis II reconnaissance and target acquisition aircraft has once again been spotted over neutral waters of the Black Sea, six days after its last flight, a source in the European Union’s air traffic control services told TASS.

"The plane that was last observed flying in the area on April 17 has once again been spotted over neutral waters of the Black Sea," he said. According to the source, the aircraft took off from an airfield in Romania’s Constanta, crossing areas monitored by Romanian and Bulgarian air traffic controllers.

"The plane has circled the area several times without entering any country’s airspace," the official noted, adding that the plane was keeping away from civilian flight corridors.

Earlier in the month, a Bombardier Challenger 650 Artemis II aircraft was spotted over the Black Sea on several occasions, including together with a British Boeing RC-135W Rivet Joint reconnaissance aircraft.