Rangithui/Colonial Knob is a popular walking area, and police said they understand this incident may leave locals concerned.
Police are following positive lines of inquiry, but are seeking the public’s assistance to help locate the alleged offender.
“The man was wearing a dark-coloured, long-sleeved top, dark-coloured track pants and a cap,” Evans said.
Police will be conducting reassurance patrols in the area in the coming days.
If you were in the area at the time or have footage of someone matching the suspect’s description, please contact police.
You can report information to police via 105, either over the phone or online, referencing file number 250618/1395.
Information can also be provided anonymously via Crime Stoppers on 0800 555 111.
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