Many people in France are reporting getting needled out of the blue at nightclubs and concerts over the past few months. Nobody knows who is doing it, why they are doing it, or whether the victims have been injected with any kind of drug or any kind of substance at all. To boost awareness, club owners and police are working together, and a rapper even paused his recent act to warn concert-goers about the potential of needle attacks. A spate of “needle spiking” in France is being investigated by the British government, and police in Belgium and the Netherlands are also looking into a few cases.

Symptoms of nausea, dizziness, and intense pain are all reported by the victims, most of whom are women, after a night out on the town. They later discover a needle prick on their skin surrounded by a blue circular bruise. Approximately 60 such occurrences have been reported in nightclubs since the beginning of April, according to a police source, and the actual number is likely far higher. French paramilitary police force, the gendarmerie, said it couldn’t provide any countrywide estimates since the data hadn’t been adequately analyzed because it is largely active outside of metropolitan cities. Prosecutors say that 45 incidents have been registered in Nantes since the middle of February.

France’s Atlantic coast and southern regions were also hit with complaints from people who claim to have been harmed. GHB, sometimes known as “liquid ecstasy” or “date rape drug,” has not been detected in any of the victims’ blood samples. This is a narcotic that would-be rapists may add into their victims’ drinks. He told AFP that no additional dangerous material had been found in the samples, and that no one had been arrested as a result of the examinations. However, experts warn that GHB evaporates from the bloodstream within hours of use. In several cases, a sex attack followed the needle attacks, according to a police source.