Prime Minister David Cameron has set out his plans to introduce greater powers to tackle extremism, saying that the UK has been a ''passively tolerant'' society for too long.

The measures, in a new counter-extremism bill, include banning orders against individuals and groups that promote extremist views which undermine British values.

The BBC's Gordon Corera reports on the radical Islamist preacher Anjem Choudary who some believe has prompted the government's actions.