Nightclub needle attacks puzzle European authorities

Youths walk on quay Des Anneaux near the Warehouse nightclub in Nantes, western France (AP)

Across France, more than 300 people have reported being pricked out of the blue with needles at nightclubs or concerts in recent months.

Doctors and multiple prosecutors are working on the case, but no-one knows who is doing it or why, and whether the victims have been injected with drugs – or indeed any substance at all.