An undercover officer smashed a terror cell drumming up support for Islamic State extremists after he spent nearly two years infiltrating meetings to record their inflammatory speeches.

The officer identified only as Kamal forged close relationships with the Luton chapter of a banned group linked to hate preacher Anjem Choudary as he collected evidence, a court heard.

Equipped with a false identity including a fake name, fake wife and fake business, he spent 20 months recording hundreds of encounters, and meetings where scores of people heard speeches praising Islamic State in Iraq and Levant (Isil).