A wave of “syringe attacks” overshadowed the celebrations of the Fête de la Musique on the evening of June 21, which saw millions take to the streets across France and "unprecedented crowds" in Paris.

Authorities have launched a nationwide investigation and detained a number of suspects, but the motive, such as whether drugs were involved, and the full extent of the harm remain key questions, according to France 24.

Who did it?

France police have detained 12 suspects in connection with the "syringe attacks," who are believed to have targeted around 50 victims, according to a police source, reported Le Monde.

Beyond these, more than 370 people were detained during the festival on various charges, including nearly 90 in Paris.

Two men were specifically arrested in Metz on suspicion of syringe attacks.

One was caught with a syringe and a woman, who reported being stabbed, recognised the other. The local prosecutor’s office in Metz stated that one of the alleged suspects, a 20-year-old man, was previously known to police for violence.

Feminist influencer Abrège Soeur had warned online before the festival about social media calls for women to be targeted with syringes, though the origin of these posts was uncertain, according to The Guardian.

Why was it done?

The exact motivation remains unclear.

Officials have not confirmed if these were cases of so-called needle spiking with date-rape drugs such as Rohypnol or GHB, which are used to incapacitate victims for sexual assault.

This wave of incidents echoes a similar surge in reports of alleged syringe attacks in 2022 in clubs, bars, music events and even theatres, prompting government advisories for vigilance and immediate police reporting along with toxicology tests if drugging by syringe was suspected, according to The Guardian.

During the 2022 Fête de la Musique, many women complained about syringe attacks.

Hundreds more were reported throughout the year in cities like Nantes, Grenoble and Toulouse.

A 2022 police memo noted that syringe marks were typically found on the arms, buttocks, or back, often without the victims seeing their attacker.

Were drugs involved?

While officials have not confirmed the involvement of date-rape drugs, at least three people reported feeling unwell and some victims were taken to hospital for toxicological tests, reported France 24.

In Paris, investigations were opened after three individuals, including a 15-year-old girl and an 18-year-old male, reported being pricked in three different locations and all three reported feeling unwell.

Local public radio station Ici France reported that several young women in Évreux and Rouen in Normandy complained of being stabbed with syringes, with one woman hospitalised with pain in her left arm where she believed a needle had been stuck. In Tours, 13 women complained to fire services about being pricked with a syringe at a music event.

Was anyone seriously hurt?

None of the victims of the "syringe attacks" have been reported as seriously hurt.

Outside of these incidents, 14 people sustained serious injuries during the night's festivities, including a 17-year-old found with stab wounds to the lower abdomen who was hospitalised, reported Le Monde.

13 police officers were injured during crowd control and other incidents.

Despite these disturbing reports, Paris police prefect Laurent Nunez stated that "no major incident has been reported."