Facebook Inc is again being sued for allegedly spying on Instagram users, this time through the unauthorised use of their mobile phone cameras.

The lawsuit springs from media reports in July that the photo-sharing app appeared to be accessing iPhone cameras even when they weren’t actively being used.

Facebook denied the reports and blamed a bug, which it said it was correcting, for triggering what it described as false notifications that Instagram was accessing iPhone cameras.

In the complaint filed Thursday in federal court in San Francisco, New Jersey Instagram user Brittany Conditi contends the app’s use of the camera is intentional and done for the purpose of collecting “lucrative and valuable data on its users that it would not otherwise have access to”.

By “obtaining extremely private and intimate personal data on their users, including in the privacy of their own homes”, Instagram and Facebook are able to collect “valuable insights and market research”, according to the complaint.

Facebook declined to comment.

In a suit filed last month, Facebook was accused of using facial-recognition technology to illegally harvest the biometric data of its more than 100 million Instagram users. Facebook denied the claim and said that Instagram doesn’t use face recognition technology.

 - Bloomberg