Authorities in a small city in Germany have been left stumped over why needles continue to turn up in food bought from a single supermarket.

Over the Christmas and New Year period, police in Offenburg, in south-western Germany issued press releases about how customers found pins in their food bought in the store.

On 28 December, an initial report of a needle in a bagel found earlier that month had led another person to come forward having found a needle in another bakery item.

Police said the products had come from the same shelf and luckily no one was injured.

Food inspectors said that the products had been correctly delivered and that the needle could only have been added in the supermarket. The store added extra security measures but the incidents continued.

On 29 December, police said a third person had come forward, this time having bought a packet of sandwich baguettes the week before and finding a needle in one of the rolls, had sent the product back to the manufacturer without alerting the supermarket or law enforcement.

Then on New Year's Day, Offenburg police said that two more people had come forward having found needles in their food over the weekend. The first was a bread package bought on 16 December but the other was a meat product, with a newly purchased salami snack found to have been tampered with.

Police said that the supermarket has further tightened security while investigators work to discover the source of the potentially dangerous needles. Speaking to, a police spokesperson said: "we are doing everything we can to find out".

Metal detectors may be brought in to help inspectors check products, while the local consumer protection agency told customers to be vigilant and report any products that they think may have been tampered with.