A video has been released of the suspected offender involved in a "repugnant" sex motivated attack on a female jogger in St Mary's Bay.

Auckland Police have released the video on social media in an attempt to help them with their ongoing inquiries into the incident on Friday morning.

The woman was jogging at about 5am on the track alongside Auckland's Northern Motorway, heading towards the central city, when the man has grabbed her, dragged her into some bushes near St Mary's Rd, strangled and sexually assaulted her.

A passing cyclist heard her screaming and came to her aid and courageously chased the fleeing offender.

The offender then ran off in the direction of Swift Ave and St Marys Bay Rd. He was last seen jumping over a fence, heading in the direction of Swift Ave and Hackett St, through the rear of properties.

Detective Senior Sergeant Glenn Baldwin said the footage clearly outlines where police believe this offender has come from to carry out this attack and which way he has fled.

Baldwin said the footage has revealed that the offender was on Beaumont St, opposite Victoria park, prior to the incident.

He is described as being a male, dark skinned, with short black hair, 175 – 180cm tall and of slim build.

He is believed to have been wearing a dark hoody with writing, a cap and possibly aged between 18 and 38-years-old.

"We are continuing to interview witnesses and persons of interest but unfortunately have not yet identified the person responsible for this repugnant attack," Baldwin said.

"We are continuing to make a number of enquiries but still need our community to contact us with any information.

"We believe someone will know this man, and we are keeping an open mind as to why he was in this area."

Baldwin said it was possible the man worked in the area, or was travelling through the area before or after work.

"Or he could have just been in the area after a night out," he said.

"We want to hear from anyone who saw anything, even if it was minor and we ask residents in the St Mary's Bay area who have CCTV cameras to contact police."

Baldwin said police are continuing to support the victim and the cyclist who intervened.

"Both are very traumatised by what has happened," he said.