The head of a British intelligence agency has said that some of the Internet companies has been ignoring the way the web is being used by "extremists".

Robert Hannigan, the head of Government Communications Headquarters (GCH), said technology giants such as Google, Facebook and Twitter are "in denial" about groups such as al-Qaeda and the Islamic State of Iraq and the Levant (ISIL), putting propaganda online with apparent ease.

Al Jazeera’s Phil Lavelle reports from Dublin.

Source: Al Jazeera