Three men facing charges over the murder of police employee Curtis Cheng at Parramatta, in Sydney’s west, have also been charged with being members of a terrorist organisation.

Mr Cheng was shot dead by 15-year-old Farhad Jabar outside NSW police headquarters in October.

Jabar was killed when police officers returned fire.

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It was later revealed the teenager had been radicalised and his attack had been linked to terrorism.

On Wednesday, the NSW Joint Counter-Terrorism Team charged Talal Alameddine, 23, Mustafa Dirani, 22, and Raban Alou, 18, with being members of a terrorist organisation.

The Australian Federal Police and NSW Police have declined to name the organisation.

The men are currently in custody at a Goulburn jail having been previously charged with offences relating to Mr Cheng’s murder.

Dirani is also charged with knowingly participating in the supply of a pistol and knowingly participating in a criminal group.

He is due to appear in Parramatta Local Court on Thursday.

Alameddine is also charged with knowingly participating in a criminal group, supplying a pistol to an unauthorised person, acquiring a pistol contrary to a Firearm Prohibition Order and hindering the discovery of evidence.

Police said Alou had previously been charged with aiding, abetting, counselling and procuring the commission of a terrorist act.

Alou and Alameddine are due to appear in court next month.

All have been bail refused.