Officials say a passenger aboard an Istanbul-bound Ukrainian flight claimed he had a bomb and tried to divert the plane to Sochi. Habib Soluk, the Turkish Transport Ministry undersecretary, told reporters that the man rose from his seat, shouted that there was a bomb on board and tried to enter the locked cockpit.

The pilot switched on the hijack signal (NBC News' Richard Engel reports pilots turned off their inflight monitors), then an F-16 military jet escorted the plane down. The plane has now landed at Istanbul’s Sabiha Gokcen airport, but the 110 passengers are reportedly still on board. There have been reports that the would-be hijacker has been subdued, but that hasn't been confirmed yet. Pegasus Airlines confirmed in a statement that there was a “bomb threat” aboard the flight.