One witness described pandemonium on Twitter, writing: "When a group of random people start running in London, you run as well".
Other have described "scary" scenes and "siren everywhere" as emergency services descend on the scene.
Daily Star reporter Sarah Buchanan was caught at the scene when it happened.Here's another quote of you want it.
"I was walking down the escalator and everyone started running in opposite direction yelling 'fire, fire'.
"It smelt like petrol or gas not just burning.
"They evacuated the station. Fire engines have turned up.