UK spy agency GCHQ reportedly snooped-on Facebook and YouTube activities of users, documents released by NSA whistleblower Edward Snowden have revealed.

The documents have revealed that the GCHQ monitored YouTube video views, Facebook 'likes' and Blogger visits among other activities in real-time.

According to the BBC, the alleged programme, codenamed Squeaky Dolphin, exposed recently, pointed that the GCHQ and the US' NSA took help of 'leaky mobile apps' like Angry Birds, Facebook, etc. to pull out users' data.

Post revelations, Facebook has started encrypting its data, but Google' YouTube and Blogger services remain unencrypted and the search giant's legal chief David Grummond expressed shock, surprise and outrage over the alleged revelations.

The documents revealed commercially available software Splunk Dashboard was used to provide real-time analysis of how people use YouTube, Facebook and Blogger, allowing organizations to 'listen' to their own data.

The report said that both YouTube and Facebook have denied giving permission to the GCHQ to access user data.