The latest complaint, filed with federal regulators, claims that the social media giant’s ‘Tag Suggestion’ feature violates privacy rights through facial-recognition software.

The complaint, filed to the Federal Trade Commission by a coalition of US consumer rights organisations led primarily by the Electronic Privacy Information Centre, takes issue mainly with the feature which helps users identify people in photographs they have uploaded by suggesting names of people that the software recognises. The facial recognition software compares faces in photographs with an enormous amount of faces in a database.

The complaint alleges that Facebook “routinely scans photos for biometric facial matches without the consent of the image subject”, using the confirmations by users to further “advance its facial recognition techniques.”

According to the complaint, these practices ignore clear preferences of many users, and are illegal in many US states and other parts of the world.

Facebook denied the claims, with Facebook deputy chief privacy officer Rob Sherman saying users could opt out for themselves and that “our face-recognition technology helps people manage their identity on Facebook and make our features work better for people who are visually impaired.

The complaint is similar to one filed in 2011 that did not lead to further action, and several private lawsuits that had been filed over the facial recognition software, which were unsuccessful.

This complaint is the latest in a long string of issues relating to Facebook users data, the most serious of which include charges that Facebook allowed personal data of 87 million users to leak to Cambridge Analytica, a firm potentially responsible in part for the 2016 election of President Donald Trump.

Facebook’s CEO, Mark Zuckerberg, is set to testify at two congressional hearings next week.