The Russian plane, a Tupolev Tu-134 airline, reportedly in Russian military service, was flying en route from the Kaliningrad exclave to ''mainland'' Russia, in international airspace over the Baltic Sea, BNS reports, quoting the Lithuanian Ministry of Defence.

Since the Kaliningrad Oblast is a highly militarised zone bordered by two EU states (Poland and Lithuania), Russian planes flying to or from there often have no other option but to fly over the Baltic in order to get home, making such incidents common, involving NATO aircraft including the Eurofighter Typhoon in the service of countries including Germany and the UK.

The NATO duties are conducted from two bases, at Ämari, west of Tallinn, and at Šiauliai, in Northern Lithuania.

Often such aircraft do not have a functioning transponder on the necessary wavelength and/or do not maintain radio contact with regional air traffic control, though it is reported that this plane did not infringe those requirements. The flight had, however, reportedly not pre-filed a plan.

The Tupolev Tu-134 (NATO handle: Crusty) is a twin-engined jet airliner built in the former Soviet Union from 1966 to 1989. Other current military operators include Kazakhstan and Syria, and the plane was formerly in civilian service in Estonia, operated by Estonian Air.

Estonia, Latvia and Lithuania joined NATO in 2004.