Air, land, and sea searches will continue into the evening as teams scour the west Auckland beach suburb of Piha for a missing 21-year-old woman.

Kim Bambus was last seen on Friday morning when she left Ponsonby to go running on the Ahu Ahu Track.

Police say there are cliffs near the track and surf life saving crews will search the shoreline, joined by the police Eagle helicopter from above.

Police say they're looking into Kim Bambus' background aren't ruling anything out - including foul play.

She was last seen wearing a dark coloured jacket, pink exercise top, black shorts, and black and white Nike exercise shoes. Her hair was tied up in a ponytail and she was carrying a large water bottle.

"If Kim isn't found tonight, then we'll be back tomorrow," Detective Inspector Hayden Mander said.