A Su-30 fighter jet crashed during a training flight on Saturday in Russia's Kaliningrad region, killing the two pilots on board, RIA news agency quoted the Defense Ministry as saying.

"The Su-30 aircraft crashed in a deserted area. The flight was being carried out without ammunition. The crew of the aircraft died," the ministry said in a statement cited by RIA.

It said the likely cause of the crash was a technical malfunction but gave no further information.

Kaliningrad is a Russian exclave sandwiched between Poland and Lithuania, both NATO member states, on the Baltic Sea.