Helicopters being used by police in an anti-football hooligan exercise crash in snowy weather near Berlin Olympic Stadium pilot died.

One of helicopter pilot died, following the accident at 10.30am local Germany time.

Onlookers described how one aircraft ended up on its side and how the rotors of both helicopters were destroyed.

One helicopter appeared to be a blue police Puma helicopter while the other appeared to be a military model.

German media said four people were hurt in the snowy weather crash, with two of those listed as seriously injured.

An injured officer was seen walking with blood streaming from facial wounds.

One eyewitness told N-tv: “It was a real snowstorm, suddenly we heard a bang and someone shouted, ‘Everybody down.’

“Then there was blood everywhere. Next to me was a huge puddle of blood.”

According to AP, some 400 federal police officers were conducting a training exercise on dealing with football violence.

It is understood around half of the officers in the exercise were pretending to be football hooligans.

Federal Police spokesman Frank Brochert confirmed there “was an incident during an exercise” and that emergency crews were on the scene.

Interior minister Hans-Peter Friedrich visited the crash site and said: “Our thoughts are with the families of the victims.”

Bild said it appeared one pilot had become disorientated in the snowy Berlin conditions and crashed into the other helicopter.

The helicopters collided at low altitude, shortly after they passed over the affluent Charlottenburg residential area in the west of the city.

The crash occurred further west on an area known as Maifeld, which is adjacent to the historic sporting stadium.

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