Communications Minister Malcolm Turnbull believes the ABC risked the security of audience members by allowing a former terror suspect to appear on its Q&A program.

The government will investigate how Zaky Mallah was allowed to ask questions of the panel, with Mr Turnbull describing the incident as “undergraduate playing at tabloid journalism” to shock viewers.

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Mr Turnbull denied the government was trying to encroach on the editorial independence of the ABC, saying the Q&A program “should do better” and he simply wants to know how it happened.

In a heated interview on the ABC’s Insiders program on Sunday morning, Mr Turnbull said host Barrie Cassidy had “lost the plot” after a series of questions about the government’s attack on the national broadcaster.

Mr Turnbull claims Mallah being allowed into the audience was a security issue because Q&A was a “very high-profile target”.

He questioned why Q&A‘s producers would choose the “least reputable, most discredited and arguably one of the most dangerous individuals” to participate in a debate on proposed citizenship laws.

“The answer, I suspect, is because in a sort of undergraduate playing at tabloid journalism style, they wanted to create the biggest shock and awe and sensation,” he said.

Mr Cassidy asked Mr Turnbull how permitting Mallah to join the audience was any different to allowing him to walk through a shopping centre.

“Are you pulling my leg? After the Martin Place siege, you are saying to me there is no security issue with putting Zaky Mallah in a live audience?” Mr Turnbull said.

“If you can’t see that, I’m sorry.

“Seriously, you’ve lost the plot there with all due respect. This is a high-profile audience, very high-profile target. This is a fellow that has threatened violence in the past, threatened to kill people, gone to jail for it.”

Parliamentary secretary Steven Ciobo, who clashed with Mallah on Q&A, accused the ABC of lacking balance and played down suggestions freedom of speech was under attack.

“Could you imagine if Zaky Mallah had used that national platform to stand up and say that he wanted to see two woman gang raped?” he told Network Ten’s Bolt Report.

“Could you imagine the uproar? There wouldn’t be any spurious arguments about the right to freedom of speech.”

On Q&A, Mr Ciobo told Mallah he’d be proud to be part of a government who kicked him out of the country.

Fellow panellist, Labor frontbencher Joel Fitzgibbon, accused Mr Ciobo of deliberately inflaming the situation when confronted by Mallah.

“He was seeking a rise out of Zaky Mallah because he knew what the outcome would be for the ABC and his … electoral prospects,” Mr Fitzgibbon told Sky News.

Mallah in 2005 was cleared of terrorism-related charges involving a suicide attack on a commonwealth building.

He admitted to threatening ASIO employees and spent two years behind bars.

Two days after the Q&A broadcast and after admitting error, the ABC re-ran the program.

– with AAP