Gatwick Airport’s North Terminal was evacuated “for the protection of the public” this morning after a gun was found.
Hundreds of people were photographed standing outside the airport in the rain after being told to leave the airport at around 10am.
Witnesses said armed police were seen arresting a man believed to have a gun in his bag.
Sussex Police confirmed the 41-year-old from France was being questioned after “what appears to be a firearm'' was discovered at the airport.
He had been seen acting suspiciously before throwing a package in a bin.
A spokesperson for Sussex Police told The Independent the evacuation was a precaution "to protect the public" sparked by the discovery of a "suspicious article".
A statement from the force said officers were called at 9.30am following "suspicious actions by a man who discarded an item in a bin". Bomb disposal experts destroyed the idem in a "small" controlled explosion.
"Personal items and what appears to be a firearm were recovered and have been removed for forensic examination," a spokesperson said. "However, the viability of the weapon has yet to be established.
"A 41-year-old man from Vendôme in France was arrested at the scene at the time of the report on suspicion of firearms offences. He was 'landside' at the airport and had not checked in or passed through any passport or security checks."
Detective Superintendent Nick May said that although security had been increased following the Paris attacks, it was too early to speculate on the suspect's intentions.
"The man is being interviewed as we try to determine the circumstances of the incident, but at this time it is too early to say what his intentions, if any, were," he said.
"However, given the events in Paris on Friday evening, there is heightened awareness around any such incident and it is best that we treat the matter in all seriousness.
“We are aware that there is concern about what has happened in France, but the general threat level remains the same and people should be aware as usual of anyone acting suspiciously.”
Tim Unwin, a geography professor at the University of London, wrote on Twitter that the incident started shortly before 10am, when the terminal’s first floor was closed and check-in was moved.
He said the full evacuation started around 10 minutes later. Passengers and staff are now being allowed to return to Gatwick's North Terminal.
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