The station, which is the busiest in Europe, was evacuated as authorities attempt to deal with the situation. The men are reported to have arrived at Gare du Nord on a train from Valenciennes, a town in northern France close to the Belgian border. French intelligence allegedly received information on Friday that the men were due to arrive in the country and were planning to carry out an attack.

TWITTER Images on social media show armed police deployed around the station

DAVE JAMES PHILLIPS Police officers and vehicles outside Gare du Nord

Since Friday there have been reported sightings in Paris, Bordeaux and Marseille, each of which prompted a major police operation. Images on social media show armed officers positioned outside the station amid reports of a huge police presence inside the terminal. Police confirmed that a security operation was underway and urged people to follow the instructions of the authorities. Policeconfirmed Gare du Nord was gradually reopened early on Tuesday morning, although they offered no further details.

DAVE JAMES PHILLIPS Images on social media show a heavy police presence outside the station

Claire Downey, 19, told Express.co.uk: “I got off of the metro at Gare du Nord and didn’t see anything out of the ordinary, then I walked into McDonald’s for a milkshake and by the time I got out there were police everywhere. “I live right next to Gare du Nord, so as I was walking home the police stopped me and said I could not pass. “As I was trying to explain that I lived there, loads of officers ran out from the metro exit and the station itself saying to run so we all ran down the street. “I had to walk back up to get home, so I did and an officer escorted me home. He told me not to worry but to stay indoors.”

GETTY FILE IMAGE Paris' Gare du Nord is Europe's busiest train station

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