Passengers climbed out of the smashed windows of a tube train at Clapham Common station in London on Friday evening amid a fire alert. A video posted on social media shows a man with a hammer cracking one of the Northern Line tube windows to allow travellers trapped inside to get out, while other videos show smashed windows. London fire brigade said crews attended the scene at Clapham Common station but found no sign or evidence of a fire. It said: “Investigations are ongoing but the report of smoke is believed to have been caused by the train’s brakes.” Passenger Nigel Ingofink told the PA news agency he was on the affected tube when the incident happened at around 6pm. He posted a video to Twitter showing broken windows on the tube and passengers filing out of Clapham Common station. He captioned the footage “Clapham Common tube emergency! Just evacuated.” He told PA: “The train stopped suddenly with half the carriages in the station and there was no movement or announcements for several minutes. “Then the lights went out and we could hear screaming towards the rear. “Finally the driver told us to walk to the rear of the train and we exited a set of open doors to witness the scene of broken windows on the platform where other passengers had obviously panicked. “There was a strong smell of burning around the carriages with the broken windows.” Ingofink said there was “ultimately an orderly evacuation”. London fire brigade said about 500 people left the train before firefighters arrived and it had not received any reports of injuries. A TfL spokesperson said: “We’re sorry for the distress caused at Clapham Common. “We are investigating the details of this incident.”