Data about people using the Metropolitan Police’s website to report sexual offences, domestic abuse and other crimes has been passed to Facebook, it has been reported.

The information, which included the type of offence being reported as well as a user’s Facebook profile code, was sent to the social media giant via a tracking tool called a Meta Pixel which was being used on the police force’s website.

The data was sent despite the online form for victims and witnesses to report offences apparently being “secure”, according to the report in The Observer.

The embedded tracking tool also sent details to Facebook about content viewed and buttons clicked on webpages linked to contacting police, accessing victim services as well as advice pages for crimes including rape, assaults, stalking and fraud.

Dame Vera Baird, the former victims’ commissioner, told the newspaper: “You think you are dealing with a public authority you can trust and in fact you are dealing with Facebook and the wild world of advertising.”

The Observer analysis found that Norfolk and Suffolk police forces also shared data about people accessing sensitive webpages.

The Met Police said that it used the Meta Pixel facility for recruitment campaigns and would be removing them from all other pages.

A force spokesman said: “Pixels have been implemented on our website homepage and career webpages to enable relevant recruitment advertising to be served to people who have indicated an interest in a career at the Met.

“At no point is the personal data inputted by an individual reporting crime ever shared with third parties.

“A Meta Pixel was placed on the Met Website in June 2023 relating to a recruitment marketing campaign and we are taking steps to remove Pixels from any non-recruitment specific pages to avoid unnecessary concern.”

He added: “The MPS website is part of the Single Online Home which uses industry standard techniques to understand the user journey through our website which enables us to understand where our users find navigation difficult and improve our service to the public.

“The technology used to do this does not under any circumstances disclose the content of information entered nor does it disclose the personal details of the individual using the service.

“For the avoidance of doubt an IP (internet protocol) address does not identify an individual by name or specific geographic address and IP addresses are typically not static.

“The analytical data captured is reserved to the website operator (the police), at no stage enters the public domain and no commercial organisation, including the providers of the analytic and advertising services, are able to utilise the same.

“The MPS has used additional services to serve more specific advertisement data to individuals who may, for example, be interested in applying to join the police.

“Again this data neither identifies the individual by name nor does it share any information that they have provided via any online form with a third party.

“It is important that the public have confidence in our services so we are reviewing the use of analytics and advertising features.”

A spokesman for Meta, which operates Facebook, said: “We’ve been clear in our policies that advertisers should not send sensitive information about people through our Business Tools.

“Doing so is against our policies and we educate advertisers on properly setting up Business Tools to prevent this from occurring. Our system is designed to filter out potentially sensitive data it is able to detect.”

Norfolk and Suffolk constabularies have been approached for comment.

A previous Observer investigation found that 20 NHS trusts had shared private information of patients with Facebook through the use of Meta Pixels with 17 of the trusts saying they would stop using them.