A major police search is under way after a knifeman sparked panic among rush-hour commuters at a south west London Underground station.

The alarm was raised shortly after 7pm on Monday when a man was seen carrying a blade at Balham station before vaulting the barriers and escaping. British Transport Police (BTP) have launched an urgent manhunt and are appealing for witnesses from the Northern Line service and the station concourse.

Footage shared across social media shows terrified passengers ducking down on tube carriages and shielding themselves behind seats. In one clip, a commuter can be heard shouting “oh my god” and asking “has he gone yet?” while others cautiously peer down the platform as the suspect runs from the scene.

One witness described the fear on the platform in a message posted online. They wrote: ‘A situation has just happened on the Northern Line. The tube was about to leave Balham station (going to Morden) people started screaming down the platform and banging on the tube windows.’

According to the same account, a warning soon rang out among the crowd. Someone screamed: ‘he has a knife, get off the train’. The witness added: ‘If you have any information on this could you please share? I don’t think anyone was injured but hoping everyone is ok and safe!’

BTP confirmed the seriousness of the incident and said the knifeman was still being sought. The force stated:

‘Officers were called to Balham Underground station at 6.11pm yesterday (17 November) following reports of a young man with a knife at the station who jumped the barrier and fled the station.’

In an updated appeal, a spokesperson for the force said:

"Urgent enquiries into this incident are ongoing. Anyone who witnessed the man or has information is asked to contact British Transport Police by texting 61016 or by calling 0800 40 50 40, quoting reference 511 of 17 November."

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