A bomb threat against an Austrian Airlines flight from Tel Aviv to Vienna on Sunday, October 18, forced the plane to divert to Bulgaria, according to Bulgarian authorities and the airline. The Austrian Airlines crew decided to make an emergency landing in Sofia after reportedly receiving a bomb threat as they neared Romania, Bulgaria's transport ministry said in a statement, adding that the passengers were evacuated from the aircraft after landing. The Bulgarian air force scrambled a MiG-29 fighter jet to escort the airliner as part of established procedures, the transport ministry said.

The airline told Agence France-Presse that 51 passengers and six crew were aboard the flight, and that a security search of the aircraft –an Airbus A320 – was launched after it safely landed in Sofia about a half hour after the threat. "Once the search of the aircraft is complete, the passengers will be rebooked onto alternative flights as quickly as possible," the airline said.

According to Flightradar24 data, the aircraft, registered OE-LZE, entered Romanian airspace at around 9:10pm before turning south and heading back towards Bulgaria, where it landed in Sofia. Data from another flight-tracking platform, ADS-B Exchange, indicates that the aircraft was transmitting squawk code 7700 – a signal for a general emergency – at around the same time.

The transport ministry said that a crisis response team has been set up and the relevant authorities have launched an investigation into the incident. In a separate incident late last month, the co-pilot aboard a flydubai airline flight headed to Tel Aviv from Dubai attacked the captain and allegedly planned to intentionally crash the plane but was stopped by the captain, passengers and crew. Last week, Croatia and Germany both scrambled fighter jets after a commercial flight from the Greek holiday island of Corfu to the German city of Nuremberg accidentally sent out a hijacking alert.