The horrifying attack happened on a Jubilee line train travelling between the Southwark and London Bridge stations, on Monday, June 30. Pictured: The person of interest

The horrifying attack happened on a Jubilee line train travelling between the Southwark and London Bridge stations, on Monday, June 30. Pictured: The person of interest

Police are investigating the incident on the Hammersmith and City line in east London yesterday at 3.30pm.

The attack happened on a South Western Railway train travelling through the Richmond and Lambeth areas of London at around 4.40pm on Tuesday, May 13. Pictured: A person of interest