Australia says a “sophisticated state actor’ was responsible for a cyberattack on Australian lawmakers earlier this month, most likely carried out by a foreign country.

Prime Minister Scott Morrison on February 18 said security officials are also investigating a breach of the networks of major political parties carried out ahead of the national election due by May.

Australian lawmakers were told to urgently change passwords after the country’s cyberintelligence agency detected an attack on the national parliament's computer network.

"Our cyberexperts believe that a sophisticated state actor is responsible for this malicious activity," Morrison told parliament.

Morrison did not name any suspect countries, but government analysts have said that Russia, Iran, and China were the most likely culprits.

"When you consider motivation, you would have to say that China is the leading suspect, while you wouldn't rule out Russia either," Fergus Hanson, head of the International Cyber Policy Center at Australian Strategic Policy Institute think tank, told Reuters.

Morrison said that "there is no evidence of any electoral interference" and that “a number of measures to ensure the integrity of our electoral system" have been put in place.

Based on reporting by Reuters, AFP, and The Guardian