One pilot died in an F-4 fighter jet crash in the Ionian Sea off western Greece on Monday and rescuers were searching for the jet’s second pilot, the Greek defence minister said.

The two-seater jet was conducting a training exercise when it crashed 25 nautical miles (46 km) south of the airport of Andravida in the Peloponnese peninsula, the semi-state Athens News Agency reported.

Greece first acquired the U.S.-made F-4, or Phantom fighter jets, in 1974.