Australian Prime Minister Scott Morrison on Monday accused a “sophisticated state actor” of carrying out a cyberattack that breached Parliament’s network and also affected major political parties, Reuters reports.

Morrison did not disclose which state he suspected of being behind the Feb. 8 attack, or reveal what, if any information was accessed. He did say there was no evidence of interference into the upcoming federal election in May. Lawmakers have been advised to change their passwords.

“Our cyber experts believe that a sophisticated state actor is responsible for this malicious activity,” Morrison told parliament. “We also became aware that the networks of some political parties, Liberal, Labor and Nationals have also been affected.”

The Australian Cyber Security Center, the government’s main cyber security agency, said it is still securing local networks.

Analysts told Reuters they suspect the breach was likely carried out by China, Russia or Iran.

“When you consider motivation, you would have to say that China is the leading suspect, while you wouldn’t rule out Russia either,” said Fergus Hanson, head of the International Cyber Policy Centre at think-tank the Australian Strategic Policy Institute, according to Reuters.

Sino-Australian relations have soured since 2017, when Canberra accused China of meddling in domestic affairs. Last year, Australia banned Chinese telecommunications giant Huawei from establishing a 5G network, citing national security concerns.

Tensions flared again last month as China detained a Chinese-Australian blogger, novelist and former Chinese diplomat named Yang Hengjun on charges of endangering national security.

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