Mandurah Detectives are investigating after a man was observed committing an indecent act at a park in Meadow Springs.
The man was observed by a member of the public at a park near Gordon Road on Tuesday, February 25.
When he realised he had been seen, he left the area.
It follows a separate incident in November, in which a 48-year-old Lakelands man was charged after allegedly approaching two young girls, aged 11 and 12, outside the toilet block at Quarry Adventure Park, also in Meadow Springs.
Anyone that may have seen the incident is asked to contact Crime Stoppers on 1800 333 000 or report online at crimestopperswa.com.au.
Police are particularly hoping to speak with a man who was riding a bicycle in the area, travelling easterly on Oakmont Avenue.