Passengers on London’s transport network are being urged to report any sexual assaults or harassment they have experienced or witnessed while travelling.

The appeal follows the successful Project Guardian week of action, between July 14-18, in which 13 people where arrested in connection with sexual offences on the Tube and bus network.

These included a man suspected of trying to photograph up a woman's skirt at Gunnersbury Station and a similar incident at Green Park.

Chief Superintendent Paul Brogden, of British Transport Police, said: "Our message is clear – we want passengers to feel confident on their journey and to know exactly where to turn when they need help. A lot of victims do not report their experiences to us, for a number of reasons. Some worry that they won’t be taken seriously, or there is little that can be done to stop sexual crime, but this is not the case – you don’t have to suffer in silence."

Project Guardian is a multi-agency initiative involving British Transport Police (BTP), Metropolitan Police Safer Transport Command (STC), City of London Police and Transport for London (TfL). Each partner works together to encourage victims of sexual offences to have the confidence to report the crime. The project also aims to create an environment on the capital’s transport network which clearly demonstrates it does not tolerate intimidation and sexual harassment in any form.

During the week of action, hundreds of uniformed officers were on patrol giving advice to commuters about Project Guardian, while plain clothes officers were deployed to identify any suspicious behaviour across the network.

Approximately 2,000 police officers and PCSOs working on London’s transport system have now been specially trained to deal with these types of cases, which has led to a 26 per cent increase in the detection of sexual offences.

Siwan Hayward, TfL’s Deputy Director of Enforcement and On-Street Operations, said: "We care about our passengers and every journey they make and will not tolerate unwanted sexual behaviour of any kind on our transport network. If someone has made you feel uncomfortable, for example, touches you in an inappropriate manner, please tell the police or a member of our staff. They can then not only target the perpetrator, but also help to prevent it happening to someone else."

To report any incident of a sexual nature to British Transport Police call 0800 40 50 40 or text 61016 with details of what happened. For an incident that has occurred away from the railway network, call 101.