Police say a woman missing for six months could have been a victim of foul play

Rowena Walker was last seen in Christchurch in August, and the 39-year-old's mother reported her missing two months later.

Detective Senior Sergeant Jo Carolan says Walker hasn't used her phone or social media since the day after her last confirmed sighting.

She says they're very worried about her for that reason - and foul play has to be considered.

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