Detectives are investigating video footage of another foul-mouthed commuter shouting racist abuse on a train.
The minute-and-a-half tirade by a brunette woman on a Manchester-London train was spotted by officers after it was posted on YouTube.
Footage entitled "My Tram Experience part 2" came to light after Emma West, 34, appeared in court over a separate web video allegedly showing passengers being abused.
Officers launched the latest hunt for a brunette woman caught shouting: "You are in my country now, talk my language."
A British Transport Police (BTP) spokesman said inquiries indicate that the video may date back two years.
He said: "Anti-social behaviour like this is completely unacceptable and we would urge anyone who is the victim of such behaviour, or who witnesses it, to call police.
"It is important that incidents are reported either as they take place or, if that isn't possible, as soon as possible afterwards as this allows us to respond and investigate quickly."
West, of New Addington, was remanded in custody until December 6 after appearing at Croydon Magistrates' Court in south London charged with a racially aggravated public order offence.
Potential witnesses are urged to contact British Transport Police free on 0800 40 50 40.