An urgent appeal has been launched after a young man was allegedly seen with a knife at Balham Underground station.
The incident was reported on the Northern line just before 6.10pm yesterday (November 17).
Officers say a man was seen with a knife who jumped the barrier and then fled the station.
Urgent enquiries are now ongoing to locate the suspect.
A spokesperson for the British Transport Police 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.”
