London's Victoria train station has been evacuated.
British Transport Police have tweeted that they are responding to a "security alert" there and that officers and sniffer dogs are on the scene.
Emergency alarms and signs urging commuters to leave the station were activated at around 6pm this evening.
Video shared on social media showed automated warnings urging commuters to leave the station.
Photos also showed crowds of commuters outside the station.
One Twitter user said: "Just been evacuated from Victoria station. Police everywhere! What’s going on?!"
Another said: “Do not go to Victoria station. There is an emergency security alert going on there. It has been evacuated!”
Transport for London said: “Victoria Rail station has closed due to a security alert. Southern Rail, South East Railway and Gatwick Express services are disrupted.
“Ticket acceptance is in place on the London Underground.”
The incident was "stood down" by police at 6.30pm.