Australia terror threat
Police talk as they guard a house that was involved in pre-dawn raids in western SydneyDavid Gray/Reuters

Security has been beefed up in Australia's parliament after intelligence officials intercepted conversation indicating that the country's senior political leaders, including Prime Minister Tony Abbott, would be targeted in terror attacks.

The threat has emerged from one of the militant networks linked to the Iraqi Isis, say Australian authorities. Reports suggest the militants were masterminding a "Mumbai-style" attack on Australia.

"As a result of intelligence there was an urgent review conducted a week or so back of security at Parliament House. Parliament House certainly is a potential target. There has been chatter amongst terrorist support networks for some time," Abbott said in a television interview.

The security measures are being put in place a day after police and counter-terrorism agencies conducted major raids in Brisbane and Sydney.

"As a result of that review, the Australian Federal Police [AFP] will be taking over security, both inside the building as well as outside the building. The advice of our police and security agencies was that an attack of this nature could take place within days," said Abbott.

Following the earlier raid, four of the 15 men arrested were charged. It is suspected that one of the accused had planned to snatch innocent members of the public to behead them openly. According to AFP, more arrests are not ruled out in the coming days.

Despite Abbott's repeated attempts to pacify the Islamic community, saying they are not being singled out, several Muslims are said to be furious and have embarked on protest rallies.

Abbott told Nine Network: "The vast majority of Australian Muslims are absolutely first-class Australians. They are valued and appreciated members of the Australian community and as my friend Prime Minister Najib [Razak] of Malaysia said recently the kind of terrorist attacks that we have seen ... are against God, are against religion, and are against our common humanity."