Federal Police have been called in after an Islamic group called for Muslims to be executed if they leave the religion.

At Bankstown Public library on Saturday a leader of the fundamentalist, Islamist group Hizb ut-Tahrir made the confronting declaration.

Now the group could be banned in Australia.

When asked, "Do you want to kill ex-Muslims?”, it is alleged that Uthman Badar, Hizb ut-Tahrir leader replied: "In Islam is clear that apostates do attract capital punishment, we don't shy away from that.”

View photos When it is alleged that Uthman Badar, Hizb ut-Tahrir leader, replied to the question: More

View photos The group may now be banned. Source: 7 News More

Hizb ut-Tahrir has a draft constitution it wants adopted in Australia. Article 7.3 reads: “Those who are guilty of apostasy from (or leaving) Islam are to be executed.”

Uthman Badar has spent nearly a decade promoting radical group, but when Seven News approached him today he remained silent.

The admission terrified a former Muslim who was at the meeting.

"The main reason that I left my own country was that I was worried about my own safety,” said ex-Muslim, Shakil Ahmed.

“And now that I've come over here I know that they're the same people, they're already over here and they want me dead as well."

Also at the meeting was his friend, who fled Bangladesh after he was put on a death list for criticising Islam.

View photos Ex-muslim, Shakil Ahmed, speaks out about his concerns. Source: 7 News More

"They are banned in Germany, they are banned in Turkey, they are banned in China, all those countries, so why not in Australia? Because they are dangerous,” said death list target Shubhajit Bhowmik.

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