Armed officers have stormed a busy tube station this morning as passengers were seen being turned away.
A huge emergency response was at the scene outside Parsons Green underground station in west London.
An eyewitness told The Mirror how she arrived at the station to find "machine-gun police like you see in the airport" responding to an incident.
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She said she had heard reports of a "man with a gun on the tube".
"There were four vans, with armed police", she added.
The British Transport Police said officers arrived at around 11.30am after receiving reports of a man carrying a weapon.
However, they could not find any trace of the individual after a thorough search.
In a statement, the force said: "Officers were called to Parsons Green Underground station just before 11.30am today (7 July) following reports of a man with a weapon. Officers attended, including firearms officers, and they conducted a thorough search of the station, however no trace of the person was found."
Commuters took to social media to warn others of the travel chaos caused by the operation.
One tube passenger wrote on Twitter: "District Line: No service between Earl's Court and Wimbledon while TFL respond to a customer incident at Parsons Green.
"SEVERE DELAYS between Edgware Road and Earl's Court due to a signal failure at Putney Bridge. If you're travelling beyond Earl's Court, take the first train ..."
Another Twitter user, Stefania Ricci, responded to the post saying that she and other passengers were turned away from the station.
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