Although China has been the target of criticism for shipping poison-laced "gyoza" dumplings, Japan has recently seen its own food-safety problems brewing at home.
Sewing needles inserted in food have been discovered at supermarkets and other stores in the past few months.
The latest incident came Tuesday when an employee at a supermarket in Kitakyushu found three needles stuck to a plastic bag containing thinly sliced cabbage, police and the supermarket said.
The needles measured about 3.5 cm long, they said. The package was immediately pulled from the shelf and no one was hurt.
It was only in February that the same store found a sewing machine needle pushed into a food package, they said.
Another Kitakyushu supermarket about 1 km away discovered similar needles March 3, prompting police to launch an investigation into the three cases on suspicion of obstructing the business of the two supermarkets.
Needle discoveries aren't limited to Kitakyushu. In the town of Shimanto, Kochi Prefecture, a 68-year-old woman who had bought bread at a supermarket reported to police Tuesday that she found a 4-cm needle inside. She took a bite and felt something stiff in her mouth and spat it out, police said. She wasn't hurt.
Police said they later found more needles planted in other kinds of bread sold at the same supermarket.
A needle was also found in "dorayaki," a popular confectionary made of two small pancakes sandwiching sweet bean paste.
On March 25, a man from Kamisu, Ibaraki Prefecture, bought five pieces of dorayaki, which were individually wrapped in plastic, at a store in Itako and took them home for his family. A needle was found in one of the items, police said.