Islamic State extremist known as "Jihadi John"
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'Jihadi John' revelations spark UK security services debate

Home Secretary Theresa May has defended the security and intelligence agencies, describing them as "true heroes".

Mrs May was addressing a Conservative conference in Cardiff amid fresh questions over the secret services' handling of the Islamic State extremist known as "Jihadi John".

She spoke after the former Conservative shadow home secretary David Davis said the tactics of the intelligence agencies were "ineffective".

Chris Mason reports.

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