Two 11-year-old boys were playing in Blackbutt Reserve, Blackbutt when an unknown male approached them and asked if they wanted to ride on his bicycle at about 1pm on Saturday.

The mother of one of the children observed this interaction and approached them before the man then jumped on his bicycle and rode from the location.

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The woman later noticed the same male riding around nearby.

The incident was reported to police at about 7pm on Sunday, with officers attached to Lake Illawarra Police District commencing an investigation.

The man is described as being aged in his 40s, of a fit build, with unshaven black and white facial hair.

He was wearing a blue and black coloured top, possibly with the word 'Tehnics' on the front, red socks, black coloured gloves, a black coloured bike helmet and sunglasses.

His mountain bike is described as black with 'S-works' branding and red grips.

Police are appealing for public assistance and urge anyone with information or any motorists who may have dashcam vision to contact Lake Illawarra Police Station on (02) 4751 0299 Police or Crime Stoppers on 1800 333 000.

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