YouTube has abolished nearly 50,000 videos of radical islamist preacher Anwar al-awlaki ,who was killed in a drone strike in 2011.

Awlaki was known for preaching violence as a religious duty, although at the time of his death his family refused to accept him as a terrorist.

Awlaki posted many different types of videos on YouTube , some of them were clearly describing violence ,while others were the narration of Islam and its history.Most of the videos are believed to be removed from  the website.

If he were alive today, Awlaki would have been banned from owning a YouTube channel because he was named as a terrorist on UK and US government lists.

Anti-extremism groups lodged their first complaints about Awlaki's videos in 2009, but until last year it was still possible to find copies of his most explicitly violent material on YouTube.

A long series of complaints and reports from groups working to counter extremism detailed Awlaki's influence and called on YouTube to act.

Alexander Meleagrou-Hitchens, from George Washington University's research programme on extremism, told the New York Times that YouTube "deserved credit" for removing the videos.