Police have arrested a teenage boy as they investigate reports of women being groped on walking trails.
The arrest of the 13-year-old came after a public appeal for information about sexual touching incidents in the Narrabeen area on Sydney's northern beaches.
The boy was assisting police with their inquiries, they said late on Saturday.
Detectives are investigating eight incidents against women on walking trails between October 1 and 12.
Among the incidents were women being accosted on a popular local track at Narrabeen on October 7 and 8.
In each case, a person allegedly approached and sexually touched the woman before riding off on an e-bike.
In one of the incidents, he also made inappropriate sexual comments.
Police on Saturday released images of a person they believed might be able to help with their investigation.
The Northern Beaches Area Command said uniformed and plainclothes officers had been patrolling the area.
"We take these matters very, very seriously," Superintendent John Duncan told reporters on Saturday afternoon.
He urged anyone with video or photos of anyone acting suspiciously in the area to send them to police.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028