The man, whose identity has not been released, was a passenger on Pacific Airlines flight BL6011, supposed to fly from Hanoi to HCMC at 11:25 a.m. Thursday. He reportedly exhibited abnormal psychological symptoms and began screaming there was a bomb on the plane after taking his seat.

After the flight crew postponed the flight, the man was taken back to the airport for questioning by security forces, according to a Pacific Airlines representative.

While the plane was being checked, Pacific Airlines deployed another aircraft to take passengers from Hanoi to HCMC. That flight took off at around 5 p.m.

The incident is being investigated further, said Tran Hoai Phuong, director of the Northern Airports Authority. No other irregularity has been spotted among the passengers, luggage, crew and plane so far, he added.