Foreign powers are waging an "extensive, unrelenting" campaign of espionage and meddling in Australia, notably targeting ethnic and religious minorities, the country's spy chief warned Thursday.
The Australian Security Intelligence Organisation (ASIO) said it was struggling to cope with the threat, with its resources stretched from fighting terrorism.
Spy chief Duncan Lewis said in a forward to ASIO's annual report that over the past year there had been a "steadily worsening overall security and operational environment".
He pinpointed heightened terror fears, but also growing foreign interference which was "extensive, unrelenting and increasingly sophisticated".
Overseas powers had sought classified information on Australia's alliances and partnerships, its position on diplomatic, economic and military issues, energy and mineral resources, and innovations in science and technology, he said.
"Espionage and foreign interference is an insidious threat -- activities that may appear relatively harmless today can have significant future consequences," he warned.
Officials last week revealed sensitive data about Australia's F-35 stealth fighter and P-8 surveillance aircraft programmes was stolen when a defence subcontractor was hacked using a tool widely used by Chinese cyber criminals.
Without naming any countries, Lewis pointed to "a number of states and other actors".
"Our investigations revealed countries undertaking intelligence operations to access sensitive Australian government and industry information," he said.
"We identified foreign powers clandestinely seeking to shape the opinions of members of the Australian public, media organisations and government officials in order to advance their country's own political objectives.
"Ethnic and religious communities in Australia were also the subject of covert influence operations designed to diminish their criticism of foreign governments," Lewis added.
He said the activities represented "a threat to our sovereignty, the integrity of our national institutions and the exercise of our citizens' rights".
The report comes after recent public warnings from Australian officials about the level of Chinese government interference on university campuses.
There are mounting concerns about the way Beijing uses nationalist student groups to monitor Chinese students, and challenge academics whose views do not align with Communist Party doctrine, particularly over issues such as Taiwan and border disputes.
Foreign Minister Julie Bishop stressed this week international students were welcome but Australia was a democracy and "we don't want to see freedom of speech curbed in any way involving foreign students or foreign academics".
According to state broadcaster ABC, Beijing's intrusion into Western universities has sparked a push by Australia's closest allies, including the US, Britain, Canada and New Zealand, for a more coordinated response to the tactics.
While foreign meddling was a major concern for ASIO, so was the heightened terror threat which was placing "considerable pressure" on the domestic spy agency.
Its report said three planned attacks in Australia were disrupted over the past 12 months, while highlighting concern about the growing influence of Islamic State in Southeast Asia.