Andrew Benn was charged in January after five women aged between 16 and 20 reported that he allegedly approached them online before he met and allegedly attacked them.

The initial charges included 12 counts of sexual intercourse without consent, nine counts of assault with an act of indecency, three counts of assault with act of indecency with a person under 16, and three counts of taking or detaining a person with intent to obtain advantage.

He was handed the 28 new charges on Wednesday when he appeared before Newcastle Local Court.

The offences include 10 counts of aggravated sexual assault, 11 counts of sexual intercourse without consent, four counts of indecent assault and three counts of detain person with intent to take advantage.

The new charges are in relation to allegations from a further eight women aged between 19 and 30.

Police allege Mr Benn trawled through personal Facebook pages of young women and sent friend requests to random females before he struck up online conversations.

They also allege that after he struck up a rapport and gained their confidence, Mr Benn organised a face-to-face meeting where he is alleged to have attacked his victims. He will appear again before Newcastle Local Court on June 21.

Police believe there may be more victims who have not yet come forward. Anyone with information is urged to contact detectives on 4934 0200 or Crime Stoppers on 1800 333 000.