ISIS supporters threaten 4-year-old Prince George in online messaging app

The supporters of the Islamic State terror group have threatened to attack Prince George, the 4-year-old son of the Duke and Duchess of Cambridge, in a disturbing post shared on the encrypted instant messaging application Telegram.

On Sunday, British newspapers reported that ISIS supporters posted a message on Telegram saying, "even the royal family will not be left alone," next to a photo of the young prince.

The jihadists also added a photo of George's school in Battersea, south London, with the caption "school starts early," as well as the address of the school.

According to Daily Star, the message also featured words in Arabic taken from a jihadi song which translates as, "When war comes with the melody of bullets, we descend on disbelief, desiring retaliation."

Newsweek reported that British police are aware of the threats made by ISIS supporters against the young prince, who is third-in-line to the British throne. "The Metropolitan Police is aware of this extremist online content," the force said in a statement.

British spies are now continuously monitoring the messaging application in an effort to prevent potential terror attacks in the U.K.

Cybersecurity experts have recently warned that Telegram has become a "breeding ground" for terrorists.

"Our intelligence suggests that these threats are to be taken seriously. Over the last 12 months we have seen both official and non-offical ISIS channels move over to Telegram," said Barry Spielman, whose internet surveillance firm Sixgill has been tracking Telegram channels since the start of the year. "It's an encrypted platform, making it a lot safer to communicate without being traced," he added.

Last month, the extremists released a video challenging Prince Harry to fight jihadis and threatening to send him and his Apaches to "hellfire."

"Why don't you come here and fight us if you're man enough, so that we can send you and your Apaches to hellfire?" said a man, identified as Abu Uqayl, in the English-language clip.

Concerns have been raised about Prince George's safety in recent months after a woman filmed herself walking through the corridors of the prince's school unchallenged.

Sarah Burnett-Moore, a 54-year-old doctor, strolled into the building just days before the classes started last month. She said that the lack of security at the private school was "astonishing" adding, "I could have walked in with an IED and set it to go off."

A few weeks later, another woman was arrested on suspicion of attempted burglary, prompting the Metropolitan Police to review the security measures at the £17,600-a-year school. It is believed that school has now placed a new safety regime to ensure that the prince remains safe at all times.