Police helicopters collide in Berlin

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One person was killed and four others injured on Thursday (March 21) as two helicopters collided while taking part in a police training exercise in Berlin, the city's fire brigade said.

The accident occurred at a very low altitude in dense fog and snowfall near the Olympic Stadium in a western suburb of the German capital, a fire brigade spokesman said.

Hundreds of police officers had been taking part in the training exercise at the stadium, designed to help them deal with soccer hooligans. Many of the participants were playing the role of hooligans at the time of the crash.

The sports field where the debris landed was once used by British forces based in Berlin during the Cold War and is now used by local schools and others for various sports activities.