Romainian pickpockets are "going on tour" with popular rock bands to steal hundreds of mobile phones from fans, police say.
British tours by acts including The Libertines, Slipknot and Kasabian have been plagued by the crime gangs in recent years.
Teams of thieves get tickets for every gig, and each night take advantage of the dark and crowded venues to steal the latest smartphones from bags and pockets.
Dozens of the handsets are then handed to accomplices, who stuff them down trousers or tights before leaving the venue.
In summer months, the gangs, who can travel freely across borders thanks to EU free movement rules, turn their attention to outdoor music festivals.
The problem has become so bad that police have had to develop an early-warning system to alert forces across Europe to upcoming events they fear may be targeted.
Europol, the EU's law enforcement agency, said members of its cross-border network put warnings on an online system.
"If one country identifies a group of pickpockets 'travelling' with a special band?...? the names and pictures are distributed via a secure system,' a spokesman said.
At least 93 phones have been stolen in the past two weeks during The Libertines' UK tour, which took in Glasgow, Manchester, Cardiff, Birmingham and London.
One victim in Manchester managed to use tracking software to locate his stolen iPhone, leading police to Romanian national Marian-Irinel Leonte, 33, who was living in Birmingham.
He was jailed for 12 months after Manchester magistrates heard he stashed 33 phones in special pockets in his trousers.
- Daily mail