EasyJet flight EZY839 from Gatwick had arrived at Belfast International Airport at 21.30 BST.
Customers reported that “armed police” had surrounded the aircraft, while others boarded to inspect it - but that passengers were not told the reason for this security check, nor why disembarkation had been delayed.
Passengers told BBC News NI that they were informed by crew that they could exit the plane shortly before 11.30pm, but were instructed not to use their mobile phones as they did so.
“Passengers stranded for over two hours on board an @easyJet flight from Gatwick that landed @belfastairport around 9.35pm have now been allowed to disembark following major security operation involving armed police and fire crews surrounding the aircraft. No official statement yet,” tweeted Irish reporter Michael Fisher just after midnight on Monday.
Fisher has since clarified that he was not a passenger on the flight in question.
“Was on this flight. Unbelievable lack of communication. To be fair passengers endured the experience extremely well. As can be imagined all sorts of rumours were flying around. Luckily, there could have been a riot with a different group of passengers,” replied Twitter user Michael Greenlees.
Passenger Stephen Houston told local news that there was “no information on what’s happening from the crew - they seem to be in the dark as well”.
Another passenger told press that she got up to get her bags but the “doors opened and police came on.”
“We have been told nothing,” she said.
“The air hostesses know nothing. The captain’s door has been locked since we landed.”
easyJet confirmed that “an inbound flight from London Gatwick to Belfast International was subject to additional security checks on arrival”.
“The safety of passengers and staff is our highest priority and we apologise for the inconvenience this delay caused,” said a spokesperson from the airline.
The Independent has contacted Belfast International Airport for comment.
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