Nine people have been arrested for sexual offences in a huge police operation to tackle harassment on the London Underground and at main-line stations, it has emerged.

The week-long ‘Project Guardian’ in east London and elsewhere involved 185 plain-clothes and uniformed officers from the Met, City and British Transport police and TfL patrolling daily between 7am and 11pm, which ended on Saturday.

Officers also gathered information and provided high visibility policing as part of the operation.

One-in-six women passengers have experienced unwanted sexual behaviour, but most don’t report it, according to a TfL survey.

Project Guardian was to give women more confidence to go to police or transport staff to report incidents such as sexual touching, exposure, lewd comments, leering and harassment.

“This project is about giving them confidence to come forward and talk to us so we can target offenders,” said Transport Police Supt Nicki Watson. “We want the public transport network to be free from any kind of unwanted sexual behaviour.”

Officers carried out patrols on several parts of the Underground, including the Central line between Liverpool Street and Leyton, Liverpool Street and Oxford Circus and the Jubilee line between West Ham and London Bridge. Patrols were also carried out at main line stations including Liverpool Street and London Bridge.

Victims are being urged to contact British Transport Police on freephone 0800-40 5040 or text 61016.