Three separate incidents of contamination have been discovered at a Woolworths supermarket in Adelaide, after customers found needles and thumbtacks in various food items.
Between June 27 and July 1, needles were found in a punnet of strawberries and in an avocado, while thumbtacks were found in a loaf of bread.
Authorities say the incidents appear to be deliberate acts and are being investigated by detectives who are checking CCTV.
Woolworths has also begun a internaln investigation with the assistance of its suppliers.
There have been no reported injuries from the contamination.