Kuwait-born Mohammed Emwazi was identified by media and experts last week -- and now, reportedly, also by his parents -- as the knife-wielding masked man in online videos showing the beheadings of at least five IS hostages.

In a conversation with a member of British rights group Cage, Emwazi described how in 2009 he was interviewed by a British officer, reported to be from domestic spy agency MI5.

Asked about his views on the New York and London attacks and the war in Afghanistan, Emwazi -- speaking in a London accent -- condemned the loss of life, but complained that his interrogator did not believe him.

"I said, after what I told you, after I told you that what's happening is extremism, this and that, and you're still suggesting that I'm an extremist?" he said.

"And he started going on trying to put words into my mouth to say: 'No you're doing this, this and this, and we're going to keep a close eye on you Mohammed -- we already have been and we're going to keep a close eye on you'."