Football fans have been caught bringing illegal pyrotechnics into stadiums. When burned, Bengals can reach a temperature of up to 1,000 degrees, making them highly flammable.

In the past year, several people have been convicted of smuggling Bengals and smoke bombs at Swedish football matches. "We have a lot of countermeasures, but it is in the lack of use of these that this environment is spreading," says SvFF's chairman Fredrik Reinfeldt. But many are never stopped.