Police were called to Glenelg Primary School at about 10am on Wednesday after reports the man allegedly grabbed a female student on the arm and then fled the area.

The man was described to police as being about 180cm tall, bald and was wearing a knee-length light blue shirt, black pants, black face mask and carrying a beanie.

The victim told police the man had purple nail polish on one of his thumbs.

He was also wearing a distinctive ring on his painted thumb which is described as being black in colour with bright dots.

The man also had a black twisted bracelet on a wrist and two earrings in one of his ears.

Officers have spoken with students, staff and parents who were at school at the time of the incident, but are yet to identify any witnesses.

They have also conducted extensive door knocks and viewed a significant amount of CCTV footage in the area but are yet to identify any witnesses to the incident.

Anyone with information should contact Crime Stoppers on 1800 333 000.