The alleged incident occurred on board a Victoria line service at around 5.45pm on December 13, 2025.
A woman travelling on the train, bound for Tottenham Hale Underground station, was alerted by another passenger that a man had been taking photos up her skirt.
According to the British Transport Police, she was informed as the train approached Finsbury Park.
Detectives investigating the upskirting report have shared a CCTV image of a man they wish to speak to, whom they believe may have information that could help their enquiries.
Anyone who recognises him is asked to contact British Transport Police by texting 61016 or by calling 0800 40 50 40, quoting reference 161 of 13 December.
You can also contact Crimestoppers anonymously on 0800 555 111.
