Sydney: Australian Prime Minister Tony Abbott said on Wednesday that he was ordering a crackdown to prevent radical Islamist preachers entering the country, amidst rising tension with the Muslim community following a series of security-related raids.

Abbott, who recently warned that the balance between freedom and security “may have to shift” to protect against radicalised Muslims seeking to carry out attacks, said hate preachers would now be “red-carded” during the visa process.

The tougher new system, which he said would not require new legislation, comes on the heels of a public meeting in Sydney last week by Hizb ut-Tahrir, an international group that says its goal is to establish a pan-national Muslim state.

Conservative commentators have seized on the speech to urge greater restrictions on radical preachers.

“What we want to do is to ensure that known preachers of hate do not come to this country to peddle their divisive extremist message,” Abbott told reporters in Sydney.

“What I’m doing is declaring that we will henceforth have a new system in place which will ensure that preachers of hate can’t come to Australia to peddle their extreme, divisive and alien ideologies.” Australia is on high alert for attacks by radicalised Muslims or by home-grown militants returning from fighting in the Middle East, having raised its threat level to high and undertaken a series of high-profile raids in major cities.

Officials believe up to 160 Australians have been either involved in fighting in the Middle East or actively supporting groups fighting there. At least 20 are believed to have returned to Australia and have been said to pose a security risk.

Prominent Australian Muslims say their community is being unfairly targeted by law enforcement and threatened by right-wing groups, and there are concerns that policies aimed at combating radical Islamists could create a backlash.

The Hizb ut-Tahrir Islamist group, which has a limited following in Australia and does not advocate violence, has not cancelled a public meeting planned for Friday in Sydney, said spokesman Uthman Badar.

The group was not surprised by the new policy, he said, but it was perplexed because no foreign speakers were invited to the Friday meeting, which is set to discuss US foreign policy in Syria.

“We have long exposed government attempts to silence dissent against its unjust and brutal foreign policies and here we now see moves to legalise this silencing of dissent,” he said in a statement.

“The speakers, who have not even been announced, are all local. There are no top draw or international speakers.

“Evidently, the prime minister is not interested in facts when seeking to silence political dissent or whip up Islamophobic hysteria.” Australia also confirmed on Wednesday that it had begun flying combat operations in Iraq on Sunday, but that its jets had pulled out of their first potential strike against Daesh militants over fears of killing civilians.

Vice Admiral David Johnston said the militants were moving into built-up areas, effectively using the civilian population as a shield against the coalition’s overwhelming air power.

“Elements of them are moving into built-up areas and that clearly brings a different collateral damage issue with it that we have to manage,” he told reporters.

Last week, Abbott said Australian special forces troops would be deployed in Iraq to assist in the fight against Daesh militants, and that its aircraft would also join US-led coalition strikes.

The United States has been bombing Daesh and other groups in Syria for almost two weeks with the help of Arab allies, and hitting targets in neighbouring Iraq since August.