Facebook Disconnect, a browser extension which prevents social networking company Facebook from tracking the online behaviour of users has been downloaded 152,000 times, according to the Daily Mail.

It is known that Facebook tracks the use of other websites while a user is logged on to the social networking site. Recently, the company had to fix an error which caused the site to track online behaviour of users, even when they had logged out of the site.

According to the Daily Mail, a Facebook spokesman said, "If you’re logged in to Facebook and visit a website integrated with Facebook, your browser sends us information, including your browser and operating system information, and your Facebook user ID.

However, the spokesman added, "We use this information to help show you a personalized experience on that site. For example, when you go to a website with a Like button, we need to know who you are in order to show you what your Facebook friends have liked on that site.

"Regardless of whether you are logged in or not, we do not use the information we receive when you visit a site integrated with Facebook to track activity around the web.

Facebook Disconnect turns off Facebook’s ‘eye’ by blocking Web traffic between other sites and Facebook. The extension works in Google’s Chrome browser, Apple’s Safari browser and Mozilla Firefox.

According to the official Facebook Disconnect page, "Facebook is notified whenever you visit one of the more than one million sites on the web that use Facebook Connect and has a history of leaking personally identifiable information to third parties."

"If you’re a typical web user, you’re unintentionally sending your browsing history with your name and other personal information to third parties whenever you’re online," the company said.

Meanwhile, it is alleged that Facebook is building ‘shadow’ profiles of people do not even have an account with the social network.

The Daily Mail reported that an allegation made to Ireland’s Data Protection Commissioner (IDPC) claims that Facebook encourages users to give out non user’s personal details, like names, phone numbers and email addresses, which Facebook uses to create ‘shadow profiles’ of those people.

Facebook has refuted such allegations.