( CNN ) After a Russian fighter jet intercepted a U.S. reconnaissance plane in an `` unsafe and unprofessional manner '' earlier this week , the United States is complaining to Moscow about the incident . On Tuesday , a U.S. RC-135U was flying over the Baltic Sea when it was intercepted by a Russian SU-27 Flanker . The Pentagon said the incident occurred in international airspace north of Poland . The U.S. crew believed the Russian pilot 's actions were `` unsafe and unprofessional due to the aggressive maneuvers it performed in close proximity to their aircraft and its high rate of speed , '' Pentagon spokesman Mark Wright said . Russian state news agency Sputnik reported the U.S. plane was flying toward the Russian border with its transponder switched off , according to a Defense Ministry spokesman . Maj. Gen. Igor Konashenkov said the Russian jet flew around the U.S. plane several times to identify it and get its tail number . An official with the U.S. European Command said the claim that the transponder was off was false . Wright said the Pentagon and State Department will `` file the appropriate petition through diplomatic channels '' with Russia . This is not the first time the U.S. has complained about an incident involving a RC-135U and a SU-27 . A year ago , a Russian jet flew within 100 feet of a RC-135U over the Sea of Okhotsk in the western Pacific , according to U.S. officials who called it `` one of the most dangerous close passes in decades . '' The Pentagon complained to the Russia military about that incident . Russian and U.S. aircraft often encounter each other , both in Northern Europe as well as the area between the Russian Far East and Alaska . CNN 's Steve Brusk and Jamie Crawford contributed to this report .
The incident occurred on April 29 north of Poland in the Baltic Sea . U.S. claims it was in international airspace . Russia claims it had been taken off and was flying toward turkey .