Police are investigating after a pregnant woman was subjected to “frightening” abuse on board a commuter train.

A woman was seen acting aggressively towards the pregnant passenger, who tried to move away to another carriage but was followed by the woman and continued to have “violent abuse” hurled at her.

A 42-year-old man tried to intervene and asked the woman to stop swearing at the pregnant woman, but he was then subjected to “violent and aggressive language”.

The British Transport Police have released photographs of a woman they want to speak to in connection with the incident, which happened on board the 7.48am Southern service between London Bridge and Victoria stations on Monday, March 27.

Investigating officer, Police Constable Chris Abbott, said: “The behaviour of this woman was extremely aggressive and whilst she was not physically violent, her abuse would have been very frightening to the victim.

“No one should ever be subjected to this type of threatening and disgusting abuse and we have a number of active enquiries in place to trace the woman responsible. 

“I would like to hear from anyone who might recognise the person in the images which we have released. Any information no matter how small could be vitally important to our investigation.”

The train calls at London Bridge, New Cross Gate, Brockley, Honor Oak Park, Forest Hill, Sydenham, Crystal Palace, Gipsy Hill, West Norwood, Streatham Hill, Balham, Wandsworth Common, Clapham Junction, Battersea Park and London Victoria.

Anyone with information is asked to send a text to 61016 or call 0800 40 50 40 quoting reference 91 of 27/03/2017. Alternatively, you can contact Crimestoppers anonymously on 0800 555 111.