Australian PM's computer hacked

The Prime Minister said the breached email network was used primarily by local MPs to communicate with constituents.

"I have access to that system in my capacity as the Member for Lalor," she said.

"It's a system for parliamentarians. The work I do as Prime Minister I do on an internet system hosted by the Department of Prime Minister and Cabinet."

Earlier, the government refused to rule out the leaking of sensitive data in hacking attacks on the accounts of at least 10 federal ministers, including Ms Gillard.

Cyber attacks are emerging as the number one security threat facing Australia, with the Defence Signals Directorate revealing last year it was repelling more than 200 attempted incursions a month on defence systems.