Police say seven children were injured by flying debris as they watched a helicopter land during a police exercise in Serbia.
The accident happened in Jagodina, 100km south of Belgrade, as the children were watching an anti-terrorist unit practice.
Wind gusts caused by the police helicopter's rotor blades ripped off advertising panels at a sports stadium and the kids were struck by the debris.
Doctors say the injuries included concussions and one fractured collar bone.
APTN