University student Michelle Leng was stripped naked, bound and gagged when she was allegedly stabbed 30 times by her uncle and dumped in a blowhole on the NSW Central Coast, a court has heard.

Derek Barrett, 27, faced Burwood Local Court today accused of Ms Leng’s murder, along with a host of new charges, including child pornography.

Ms Leng was living with Barrett, who is married to her aunt, in Campsie when he allegedly took her captive on April 22 this year.

Her cousin is believed to have come to the home at some point that day, unaware Ms Leng was being held upstairs, The Sydney Morning Herald reports.

Photos of Ms Leng naked with duct tape across her mouth and wrists were found on a mobile phone linked to Barrett, police allege.

Barrett is accused of driving to the NSW Central Coast, where he visited relatives, before disposing of Ms Leng’s body at the Snapper Point blowhole, in Lake Munmorah national park, early on Sunday, April 24.

A car was filmed on a surveillance camera driving into the national park around four hours before Ms Leng's body was found floating face-down.

Barrett faced fresh charges today after video was found of Barrett purportedly masturbating over a child and Ms Leng on several separate occasions as they slept, at some point before Ms Leng was murdered.

Ms Leng had moved to Sydney five years ago from China, and was studying at the Sydney Institute of Interpreting and Translation.

Barrett’s lawyer Bill Whitby said last month his client was "shocked and upset" and will fight the murder charges.

Barrett did not appear in court and the case has been adjourned to August 10.

Barrett (left) and Ms Leng (right).