In a worrying turn of events, people across Australia have been finding small sewing needles deliberately hidden inside their shop-bought strawberries.

Eleven people have found needles in the fruit so far, and two of them were treated in hospital for abdominal pain. Authorities are desperate to find the culprit before someone else gets hurt, and they are offering a US $72,000 reward for information.

The needles were small enough to be totally concealed inside the strawberries, which makes them hard to spot. At least 11 people have reported finding needles in their strawberries, although luckily most of them spotted the danger before eating the fruits.

Who Are the Victims?

A man in Queensland, northeastern Australia was the first to comment on the problem when he published a viral post claiming that his friend had accidentally swallowed half a sewing needle while eating strawberries and had to be hospitalized. They checked the other strawberries and found another sewing needle inside one of them.

Hoani Herne, 21, from Queensland, was also taken to hospital after swallowing part of a needle and suffering severe abdominal pain, according to The Courier Mail. Nine other people in five different Australian states have reported finding needles in their store-bought strawberries, and a man in York, Western Australia reported finding a needle while washing his strawberries.

The Police are no Further Forward

It’s still unclear how the needles got into the fruit, and at what stage of production process they became contaminated.

The Queensland Strawberry Growers Association said that they suspected that the perpetrator could be a disgruntled former employee, but with contamination also reported in other states the authorities are not sure that is the case.

Queensland police are still investigating, and are keeping “a very open mind” as they interview people, according to Business Insider Australia.

Adrian Schultz, vice-president of the Queensland Strawberry Growers Association is angry at the “commercial terrorism” and has warned that it could affect the entire fruit industry. Schultz says he’s “angry for all the associated people, it’s the farmers, the people who supply them, the packaging people, the truckies with families to support, who suddenly lose their jobs…it’s far reaching.”

Investigations are still ongoing, but the police may well find it difficult to narrow it down to a suspect in the near future.