A public appeal has been launched after a man was spotted taking photos up the skirt of a fellow passenger on a Piccadilly line Tube train.

The woman was sat opposite the suspect while travelling towards Hammersmith from Hatton Cross , when the man, believed to be in his 50s, snapped pictures "directed up the woman's skirt".

The photos were taken during rush hour on the London Underground train, at around 9am on Thursday, May 17.

A member of the public saw the man taking the lewd photos of the unsuspecting victim and challenged him, but police are not sure where he got off the train.

The man is described as approximately 50 years old and of large build, clean shaven and with brown, wispy hair.

Detectives have launched a public appeal for anyone who may have witnessed the incident to get in touch.

They also asked anyone who knows someone matching the description of the suspect to get in touch.

If you have any information which could help, text the BTP on 61016 or call 0800 40 50 40 quoting reference 1800035169.

Alternatively, contact Crimestoppers anonymously on 0800 555 111.