Passengers at Stansted airport faced delays on Sunday after people arriving on a Ryanair flight went through an exit door 'left open in error'.
The error meant that the arriving passengers had to be process by departures security before moving back to arrivals, which caused delays.
A spokesman for Stansted told the Mirror on Sunday: "We are now experiencing queues in the security area with delays of up to an hour on some flights.
"We apologise for the inconvenience and hope to resolve this matter as soon as possible."
According to the BBC, a Ryanair spokesman said: "The crew of this flight correctly directed disembarking customers to the assigned gate.
"However, customers entered the airport through a door which had been left open in error.
"Ryanair fully cooperated with Stansted Airport as it rescreened departing passengers. A number of flights were delayed throughout the day due to earlier issues with de-icing facilities."
According to the Daily Mail, a host of disgruntled travellers took to Twitter to complain about the situation.
One wrote: "Pandemonium at Stansted Airport. Security queue stretches length of terminal twice!"
Pandemonium at Stansted Airport. Security queue stretches length of terminal twice! pic.twitter.com/gLZOIWJqXD- Rob Treloar (@Rob_Treloar) January 4, 2015
Another said: "Ongoing security 'issue' at Stansted Airport. Massive queues as no one can get through security. Communication over PA has not been great."
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