Islamic State has released a graphic video using the Justin Bieber hashtag on Twitter, in a worrying ploy that could see the militant organisation's propaganda exposed to the tens of millions of mostly young people who follow the megastar.

The hijacking of the Justin Bieber hashtag occurred this morning, with links to the video, titled "Message to Islamic West", also carrying the hashtags of ISIS and ISIL, by which Islamic State is also known, as well as the Bieber hashtag.

The 21-year-old has almost 74 million Twitter followers.

Initially released via the Islamic State media account, the video, seen by AAP, was still available on the social media site at the time of this article being published.


The release of the video comes after a warning from Australian Prime Minister Malcolm Turnbull this week that the online campaign against Islamic State must be considerably improved.

"... The Iraqi government and other anti-Isil forces are not reacting quickly enough to contradict Isil's online messages which have been used both to recruit new fighters and demoralise those who oppose them, and we should help them with this," Mr Turnbull said in Washington.

The 15-minute video, which was professionally produced, includes the filming of the execution of four men, who are shot in the back of the head at close range as they kneel on the ground with their hands bound.

Footage of various attacks is also shown, as are appeals for new recruits.

It also features a martyrdom video of an Islamic State fighter as he prepares to carry out a suicide bombing using a vehicle laden with explosives. The video shows the man driving the vehicle towards an enemy base, followed by a massive explosion.