Facebook admits tracking users and non-users off-site

Statement comes as company faces US lawsuit over facial recognition feature launched in 2011 and planned to expand to EU

Facebook has released more information on the social media platform's tracking of users off-site, after its CEO, Mark Zuckerberg, failed to answer questions about the process from US politicians and as the company prepares to fight a lawsuit over facial recognition in California.

In a blog post, Facebook's product management director, David Baser, wrote that the company tracked users and non-users across websites and apps for three main reasons: providing services directly, securing the company's own site, and "improving our products and services".