The most senior Australian fighting with Islamic State, Neil Prakash, has been killed in a US air strike in Iraq.
Prakash, who was at the centre of a web of recruitment that inspired terrorism plots in Australia and drove adherents to join the group in the Middle East, was targeted in the strike by a US fighter plane on Friday, Australia has been told by US officials. 
Shadi Jabar Khalil Mohammad, the sister of Parramatta shooter Farhad Jabar, was killed in a separate US strike a week earlier in Syria, government sources have also revealed. Again, they were advised of her death by US counterparts.
She was with her Sudanese husband, Abu Saad al-Sudani, who was also killed. Both were regarded as active recruiters for Islamic State.
Prakash, originally from Melbourne and also known as Abu Khaled al-Cambodi, was killed along with up to 10 other Islamic State jihadists when the building they were in was struck in Mosul, the group's de facto capital in Iraq.
His death brings to an end more than two years in which he was a key figure in pushing Islamic State's ideology into Australia.
He was a high-value target because of his prominence as a recruiter not just for his native Australia but in other countries as well. He starred in one of the jihadist group's promotional videos and was linked to extremist plots in Australia, and also to calls for lone-wolf attacks in the United States.
He was regarded as an enemy combatant under international law and is understood to have been on a so-called "kill list".
It is not clear whether Australian authorities played any role in the targeting or intelligence collection that led to either of the strikes, but Australian defence and intelligence officials work closely with US counterparts.
Prakash's death is particularly significant because, while he filled the shoes of a previous successful recruiter, Mohammad Ali Baryalei, he has no obvious successor.
Greg Barton, a terrorism expert at Deakin University, said Prakash was the last known high-profile link between the Syria-Iraq battlefield and the extremist networks in Melbourne and Sydney.
He is believed to have been involved in influencing the alleged Mother's Day pipe bomb plot in Melbourne last year and the recent alleged Anzac Day plot in Sydney. He also helped radicalise Numan Haider, who was shot dead in Melbourne after attacking two policemen with a knife.
"His death is very welcome in that he's the last prominent Australian that we're aware of who served as a key link with friends back in Australia," Professor Barton said.
"It doesn't mean the end of these exchanges, but it certainly marks the closing of the first chapter."
Prakesh was linked to the al-Furqan centre in Melbourne and the al-Risalah group in Sydney.
The fact he was killed in Iraq is significant because he spent most of his time in the group's Syrian stronghold of Raqqa. His movement underscores the solidity of the large territory Islamic State still holds spanning Syria and Iraq, despite significant territorial losses it has suffered.
A source said his death was "a very, very significant disruption to recruitment" because he was "a very prolific recruiter of vulnerable young people".