2014 Sydney hostage crisis
After the siege began, a staged exclusion zone was established with thousands of people evacuated from nearby buildings, including from the floors above the café. The Sydney Opera House was evacuated after a suspicious package was found; however, reports were unconfirmed by police. The US Consulate General in Sydney, located in Martin Place, was also evacuated. Some Sydney schools were put in "white level lockout" due to the hostage situation, which meant that no school group was permitted to leave the school grounds.
Attack on Sydney Harbour
The naval officer-in-charge of Sydney Harbour at the time of the attack was Rear Admiral Gerard Muirhead-Gould of the Royal Navy. On the night of the attack, three major vessels were present in Sydney Harbour; the heavy cruisers and , and the light cruiser . Other warships in the harbour included: destroyer tender , auxiliary minelayer , corvettes , , and , armed merchant cruisers and , and Dutch submarine "K-IX". A converted ferry—HMAS "Kuttabul"—was alongside at Garden Island where she served as a temporary barracks for sailors transferring between ships. The hospital ship "Oranje" had also been in the harbour, but departed an hour before the attack.