Woman injured by hidden spike trap on National Park walking track

An investigation is underway after a woman was injured by spikes laid in a walking track in a Western Australia national park.

The woman was walking at the rear of Wardanup Crescent in Yallingup, south of Perth, on November 18 last year.

Police said she stood on a "metal implement" which had been placed along the track.

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The spikes had been hidden by foliage, and pierced the woman's show and foot.

And second such implement was found further along the track.

Police believe they were wilfully placed.

A photo of the spikes has been released.

The investigation is ongoing, and anybody with information is urged to contact Dunsborough Police or Crime Stoppers on 1800 333 000.