A 41-year-old Frenchman has been arrested at Gatwick Airport with what appeared to be a firearm, British police said after a security alert triggered an evacuation of the busy London hub.
"Police were called at around 9.30am following suspicious actions by a man who discarded an item in a bin at the airport," Sussex Police said in a statement on Saturday (local time).
"A 41-year-old man from Vendome in (central) France was arrested at the scene at the time of the report on suspicion of firearms offences," the statement said.
"Personal items and what appears to be a firearm were recovered and have been removed for forensic examination. However, the viability of the weapon has yet to be established," it added.
Detective Superintendent Nick May said: "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."
"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," he said.
Islamic State jihadists on Saturday claimed a series of coordinated attacks by gunmen and suicide bombers in Paris that killed at least 129 people in scenes of carnage at a concert hall, restaurants and the national stadium.
Bomb disposal experts conducted a small controlled explosion after the North Terminal was temporarily evacuated, police said.
The terminal was later re-opened.
Gatwick is one of Britain's busiest airports, handling 39 million passengers travelling to 200 destinations every year and is the biggest hub for British low-cost airline EasyJet.