Prime Minister Malcolm Turnbull has joined thousands of Northern Territory locals and WWII veterans to commemorate the 75th anniversary of the bombing of Darwin.
Memorial services have been held across the NT on Sunday to mark the 75th anniversary of the attack on the Top End, which resulted in more than 200 people dying during air raids by Japanese bombers in 1942.
The attack came two months after the bombing of Pearl Harbor.
Turnbull said the bombers "rained down terror" on Darwin, realising Australia's worst fear.
"Our nation was under direct attack for the first time," he told the crowd that included US and Japanese dignitaries.
Opposition Leader Bill Shorten and Governor-General Sir Peter Cosgrove were also in attendance at the memorial service in the NT capital.
A National Day of Observance is being held on Sunday to acknowledge those who defended Australia during WWII and nine diggers have made the pilgrimage back to Darwin.
The attack brought the conflict to home soil for the first time in WWII, and signified the start of a 21-month period of devastating bombing raids on Northern Australia.
As of Sunday, nine shipwrecks around Darwin will be automatically protected under the commonwealth shipwrecks act, which protects wrecks in Australian waters older than 75 years.