A Royal Air Force aircraft carrying UK Defense Secretary John Healey experienced signal jamming near the Russian border, according to a report published Sunday by The Times.

The report said satellite signals on Healey’s government aircraft were disrupted Thursday while he was returning to the United Kingdom following a visit to southeastern Estonia.

The interference reportedly disabled the aircraft’s GPS system throughout the three-hour flight.

According to the report, the disruption also affected laptops and smartphones on board, forcing pilots to rely on alternative inertial navigation systems to determine the aircraft’s position.

Russia is believed to have been behind the incident, according to the report.

One of the pilots described the event as an unusual occurrence that he had not experienced “in a long time.” Anadolu Agency