Sydney CBD rampage accused on new charges

By Luke Costin, AAP

A Sydney man accused of murdering a sex worker, stabbing another woman and then running through the city's CBD brandishing a bloodied knife, has additionally been charged with possessing child abuse material.

Mert Ney - who was pinned down by bystanders wielding chairs and a milk crate after the alleged rampage in mid-August - has been formally charged with possessing child abuse material on a USB during the attack.

He is also accused of possessing 1.6 grams of cannabis and being armed with a knife with intent to cause a serious offence about the same time.

The 21-year-old remained quiet as he appeared via video link on Tuesday at Central Local Court where he was remanded in custody.

"He denies possessing those materials," Ney's lawyer, Zemarai Khatiz, told reporters outside court.

Ney was previously charged with murder, attempted murder and wounding with intent to cause grievous bodily harm over the August 13 incident.

Police allege he killed Michaela Dunn, 24, in a Clarence Street apartment before stabbing Linda Bo, 41, in the shoulder at the Hotel CBD.

Ney was later filmed allegedly running through the city brandishing a bloodied kitchen knife before lawyer John Bamford and others restrained him.

He's also accused of intentionally choking and assaulting a family member at Marayong on August 7.

The Blacktown man intends to defend the charges against him on the grounds of mental illness, Mr Khatiz has previously told reporters.

Prosecutors told the court on Tuesday a substantial brief of evidence had been served on Mr Khatiz but further evidence was likely to be gathered from Ney's mobile phone and medical records.

Facebook had also been issued with a mutual assistance request, the court heard.

That information is expected to be added to the brief of evidence by December 6 in time for Ney's next scheduled court appearance on December 10.

Uber and Royal Prince Alfred Hospital have already returned data after being subpoenaed.

Mr Khatiz outside court on Tuesday said his client's mental state was "still bad".

An interim restraining order against Ney, protecting the family member he's accused of choking, remains in place.