A former Knox Grammar teacher who failed to appear at a royal commission into child abuse this week has not been seen near his Nelson Bay home for days.

An arrest warrant was issued for Chris Fotis when he did not show up to give evidence at the royal commission on Tuesday.

An arrest warrant has been issued for former Knox teacher Chris Fotis. Credit:Noel Vanzetti

The 52-year-old, who taught religious education, was asked to leave Knox in September 1989 after he was arrested for masturbating outside a school at North Ryde.

The commission has heard he was also suspected of molesting a student while wearing a balaclava in 1988 or 1989. The attacker, wearing a Knox tracksuit, had hid under a bed before groping a student in a boarding house at the school.