The Special Air Service Regiment has spent the past two weeks making mock assaults on oil tankers off WA's north amid growing global concerns about the terror threat to major infrastructure projects.
Exercise Iron Moon is a big exercise involving the Australian Defence Force, Australian Federal Police and WA Police centred on Exmouth, Karratha and Dampier.
The Defence Department said the exercise aimed to improve Australia's response to an attack, including from a terrorist cell, criminal gang or enemy state.
"The training is being conducted to enhance inter-agency security response skills and ensure the ADF has the highest level of capability to support Australia's national security interests and contribute to regional stability," a spokeswoman said.
In the exercise, the SASR has boarded several oil tankers and ships to seize back the vessels from a simulated enemy.
As well as the latest weapons, the ADF put a range of military vehicles into the action, including helicopters and special purpose vessels. Live ammunition was not used.
The Defence Department would not say how many people were involved in the exercise, which started on September 15 and wraps up tomorrow.
Air Marshal Mark Binskin has revealed the North West will be home to nine defence force exercises this year, including Exercise Iron Moon.
Exercise Day Shark, which is offshore energy installation recovery training for special forces, will be held twice this year.
Three intelligence, surveillance and reconnaissance exercises will be held from Learmonth around the North West Shelf. Learmonth will also host air force personnel for Exercise Western Phoenix.
There has been a surge in terror attacks on major oil and gas installations around the world in recent years.
In January, 37 foreign workers were killed at a natural gas plant in Algeria when al-Qaida-linked militants stormed the plant.
Air Marshal Binskin, the Vice-Chief of the Defence Force, said in a letter to the Senate standing committee on defence that there would also be regular navy patrols of gas and oil installations.