The first Australian suicide bomber in Iraq killed three people in the heart of Baghdad on Thursday, an extremist group has claimed, raising the involvement of local jihadists in the spiralling violence to a chilling new level.
The Islamic State of Iraq and the Levant (ISIL) announced on an affiliated Twitter feed that a man known as Abu Bakr al-Australi had detonated an explosives vest near a Shiite mosque in a market near the middle of the Iraqi capital. More than 90 people were also injured in the blast.
A Sydney man also confirmed the suicide to Fairfax, saying he had spoken to associates in Syria who knew the man and said he had travelled to Iraq from Sydney.
The statement from ISIL lauds the man as "a migrant knight" of Islam and "a hero from the heroes of the caliphate ... who left behind the delicious and ornamental things of this world and went toward what is God's".
ISIL did not give the man's real name, but most Australian jihadists use "al-Australi" in their nom de guerre, and such official reports by ISIL are usually accurate.
Attorney General George Brandis said that if the claims proved true, it was "a disturbing development and is a further example of the dangerous and volatile situation in Iraq at present".
"This would be the second Australian suicide bomber in the Iraq and Syria conflicts," he said. "The government deplores the violent actions being undertaken by ISIL and other extremist groups in Iraq and Syria, and is deeply concerned about the involvement of Australians in these activities."
In September, a man believed to be Australian, going by the name Abu Asma al Australi, blew himself up in an attack on an army checkpoint in north-eastern Syria, but this latest bombing would be the first in Iraq, into which some Australians are known to have drifted in recent weeks.
Iraqi forces are still battling the insurgency of ISIL to the north of Baghdad, where ISIL's recent lightning advance has hit a wall. But it has long been feared that ISIL would increasingly take the fight into the capital by sending in suicide bombers.
Notorious Sydney jihadist Mohamed Elomar welcomed the news on his own Twitter account, writing "may Allah accept him".
ASIO believes that about 150 Australians are involved with extremist groups in Syria and Iraq, with about 60 fighting in the region at the moment.
The Australians believed to be in Iraq include convicted terrorist Khaled Sharrouf and two Bankstown teenagers known as Abdullah and Omar.
ASIO boss David Irvine on Wednesday expressed fresh concerns about the "tens" of fighters who have already returned home and may pose a terrorism threat.
Andrew Zammit, a researcher at Monash University's Global Terrorism Research Centre, said the latest report underscored the depth of the problem Australia was facing.
"In the past year we've seen two Australian suicide bombers in Syria and Iraq, reports of Australian jihadists murdering captives, and a flow of fighters that doesn't appear to have slowed down," he said. "This is a problem we'll be facing for a while."
Foreign Minister Julie Bishop said: "That's why we are taking this matter exceedingly seriously and we're doing all we can to prevent people from going overseas as foreign fighters . . . and we will continue to work tirelessly to prevent Australians being radicalised and coming back home with their extremist ways and ideology.''
with Rachel Olding