Australia's top cyber security agency is investigating a breach of the federal parliamentary computing network, which has forced the resetting of passwords.
There is no evidence that any data has been accessed, but the investigation remains ongoing, Speaker Tony Smith and Senate President Scott Ryan said in a joint statement on Friday.
"We have no evidence that this is an attempt to influence the outcome of parliamentary processes or to disrupt or influence electoral or political processes," the statement said.
It is understood the Australian Signals Directorate is assisting and investigating, alongside the Department of Parliamentary Services.
In March 2011, it was reported China was suspected of accessing the email system used by federal MPs, advisers, electorate staff and parliamentary employees.
Security industry sources told AAP it was possible China could be behind the latest attack.
The cyber breach comes amid revelations MPs in the UK were targeted by an attack to hack into their email and phone contact lists earlier this week.
The UK government's deputy chief whip Christopher Pincher emailed MPs warning them to ignore text messages and emails which asked them to "provide overseas contact details" or to "download a secure message app", according to BuzzFeed News.
"This is a malicious hack that accesses your contacts list and sends texts and emails to all your private contacts," the email says.
At least one Tory MP reportedly fell for the scam, with dozens of MPs added to a WhatsApp group named "Hack warning 1".
