August 12: ASIO boss David Irvine says Australian jihadists have carried out some of the "worst of the worst" extremist atrocities in Syria and Iraq and warns this could inspire young followers at home
September 1: Foreign minister Julie Bishop says "ISIS is Australia's responsibility" following intelligence up to 60 Australians could be fighting for the group in Iraq and Syria.
September 10: President Obama launches an open ended bombing campaign on Islamic State strongholds in Iraq.
September 10: Brisbane bookstore owner Omar Succarieh is arrested in Brisbane on charges of supporting terrorism. He is the brother of Australia's first suicide bomber, Ahmad Succarieh.
September 12: ASIO director David Irvine raises the Australian terror alert to high.
September 15: Prime Minister Tony Abbott declares war on "Islamic State Death Cult" and announces 200 special forces troops will be on the ground in Iraq within days, along with 400 air personnel, up to eight FA-18 Super Hornets, and two other aircraft.
September 18: Eight hundred police officers raid homes across Sydney and Brisbane, arresting 15 people in the largest counter-terrorism raids in Australia's history.
September 18: Prime Minister Tony Abbott says intelligence indicates people in Australia were planning a public beheading carried out in the name of Islamic State.
October 27: Foreign Affairs Minister Julie Bishop told Parliament "at least 70 Australians are in Iraq and Syria fighting with the terrorist organisations".
November 9: Sydney man reportedly killed fighting in Syria, bringing the suspected death toll of Australians in Syria and Iraq to 13.
December 15: Two men arrested by the NSW Joint Counter Terrorism Team in Sydney's north-west.
December 15: A dramatic siege unfolds at the Lindt cafe in Martin Place, with a gunman taking an unknown number of hostages and forcing the CBD into lockdown.
