Multiple raids carried out by some 800 police officers and security personnel in multiple Australian cities netted at least 15 suspects on Thursday in an alleged beheading plot. It's the biggest such raid in Australian history, based on evidence authorities had that the arrested suspects were planning on abducting a victim from the public at random, beheading him or her, and draping their body with the flag of the Islamic State.

Australia's Prime Minister Tony Abbott, who is currently in the country's far north, fulfilling an earlier pledge to better engage with Australia's indigenous peoples, told reporters that the raids were conducted followed directives from Islamic State commanders in the Middle East, ordering sympathizers to carry out this type of "demonstration killing."

"Quite direct exhortations were coming from an Australian who is apparently quite senior in [Islamic State] to networks in Australia to conduct demonstration killings here in this country," Abbott said.

The Soufan Group, a terrorism monitor, estimates that roughly 250 Australian nationals have joined the conflict in Syria. That number may be on the high end, though. Whatever the figure, a considerable proportion of the Australians jihadists are likely in the ranks of the Islamic State. The Herald Sun "unmasks" the identity of more than a dozen of them, including a former kickboxer and TV star.

There are half a million Muslims in Australia and only the tiniest of minorities have anything to do with the networks connecting disaffected Muslims in the Antipodes to jihadist causes in the Middle East. Terror experts say the "jihadist scene" in the country is still very small. The worst attack suffered by Australia was in 2002: a set of coordinated bombings in the Indonesian island of Bali, linked to al-Qaeda, that killed hundreds, including 88 Australians. Australian authorities have foiled four main terror plots in recent years, as News.com.au enumerates:

• An al-Qaeda and Jemaah Islamiah planned bombing of Israeli and Jewish targets in Sydney during 2000 Olympics.
• A Lashkar e-Toiba-led plot foiled in 2003. Participants collected maps of Australia’s electricity supply and sought information about making bombs.
• Two terror cells in Melbourne and Sydney uncovered by Operation Pendennis in 2005.
• A plot by an al-Shabab associated group to attack Holsworthy Army Barracks in Sydney in 2009.

The presence of Australian jihadists among the forces of the Islamic State caught the world's attention this summer following a ghastly set of images posted online, showing Khaleed Sharrouf, an Australian, posing alongside his seven-year-old son with the severed head of a Syrian soldier. "That's my boy!" read one photo caption.

WorldViews went into greater depth on Sharrouf here:

Sharrouf is probably the most well-known jihadist from Australia to join the Islamic State, which has come to the fore in recent months, claiming a vast swath of territory comprising parts of eastern Syria and northern and western Iraq. The group has gained notoriety for documenting and distributing on social media images of its slaughters — be it the heads of Assad's fighters in Raqqah or mass executions of Iraqis captured during the Islamic State's recent advance.

This is not the first time that Sharrouf, who is thought to be a schizophrenic, has participated in such grisly spectacle: In June, the newspaper Australian published images of Sharrouf posing among rows of dead Iraqis, who had been massacred by his comrades. Pointing to his example, the Australian government is seeking to implement more stringent counterterrorism laws that will make it harder for jihadist sympathizers in the country to join up with terrorist groups overseas.

Thursday's raids may be the direct consequence of Canberra's increased vigilance.