SYDNEY: Australia said Friday it is upgrading security at parliament in the face of threats from extremists who are also targeting the prime minister and other leaders, after revelations Islamic State militants were plotting “demonstration executions” in the country.

Asked about intelligence that he and other senior officials may be attacked, Prime Minister Tony Abbott said: “There is chatter, there has been chatter, amongst these networks of targeting government people."

“There is no doubt about that. That is why we are in the process of upgrading security at Parliament House in Canberra.“

Federal police are being put in charge of security at parliament, Abbott told Nine Network television after earlier describing the building in the nation's capital Canberra as “a potential target”.

“There has been chatter amongst these terrorist support networks for some time about possible attacks on government here in Australia,” he said.

Previously security was handled by in-house parliamentary security officers.

Abbott's comments came after hundreds of police officers staged a major pre-dawn operation across Sydney and Brisbane on Thursday.

Of the 15 people detained in the raids, one has been charged with terrorism-related offences and nine released, police said. At least one gun was seized, along with a sword.

Omarjan Azari, 22, was remanded in custody, charged with planning a terrorist act that prosecutors alleged was designed to “shock, horrify and terrify” the community.

The prosecution alleged the plan involved the “random selection of persons to rather gruesomely execute” on camera.

The video was reportedly then to be sent back to IS's media unit in the Middle East, where it would be released to the public.

The militants have in recent weeks broadcast video footage of three foreign nationals being beheaded in Syria.

The raids came a week after Australia lifted the terror threat level to “high” for the first time in a decade on growing concern about militants returning from fighting in Iraq and Syria.

Abbott expanded on his comments Thursday that public beheadings had been ordered by IS militants.

“Earlier this week an Australian who is a senior ISIS operative in Syria instructed his networks here in Australia to look to commit demonstration executions,” he told Seven television.

“Because we believed that a demonstration execution was likely quickly, we acted as we did to disrupt this particular network.“

The government believes up to 60 Australians are fighting alongside IS militants, while another 100 are actively working to support the movement at home.

Abbott played down fears the anti-terror crackdown would alienate Muslims.

Hundreds of people marched Thursday in Lakemba, a western Sydney suburb which is the centre of the city's Muslim community, to protest against police victimisation.

The prime minister said the demonstration was “small” and did not reflect the views of the wider community.

“The vast majority of Australian Muslims are absolutely first-class Australians,” he said.

“They're committed to our country and they have no truck whatsoever with the misguided fanatics, with the bloodthirsty extremists who we've seen on our screens in the Middle East and who regrettably do include at least 60 Australians.“

With police stepping up security under Operation Hammerhead, Abbott appealed to all Australians to carry on as normal and not be intimidated.

"The best thing people can do in the face of a terror threat here in Australia is go about normal life, because the whole point of terrorism is to scare people out of being themselves.“