ISIS fanatics have made a chilling threat against Prince George saying: "Even the Royal Family will not be left alone," it has been claimed.

The barbarous extremists allegedly posted a picture of the future king on encrypted instant messaging app Telegram with the horrifying message.

A picture of the young royal outside his $24,000-a-year school in Battersea, South London, was also reportedly shared on the app along with the school's address and the comment "school starts early."

The message allegedly also included words from a jihadi song which translate as, "When war comes with the melody of bullets, we descend on disbelief, desiring retaliation."

A Daily Star investigation uncovered the vile messages, and were told by security experts it was critical to monitor the messaging service.

Telegram has been branded a "breeding ground" for terrorists after ISIS extremists behind the 2015 Paris attacks used the encrypted messaging app to spread propaganda.

ISIS also used the app to recruit the perpetrators of the Christmas market attack in Berlin last year and claim credit for the massacre.

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