Fans of German football team Borussia Dortmund are mad, because they have raised the ticket prices. So the supporters decided to "attack" and disturb the away cup match against VfB Stuttgart. They throwed tennis balls onto the pitch. Se the video!
The away tickets cost for about $78. Many Dortmund fans also chose to skip the first 20 minutes of the game, leaving seats empty as a sign of their increasing frustration at ticket prices.