Dortmund fans look to the Galatasaray block after firework exploded on the stands during the Champions League group D soccer match between Borussia Dortmund and Galatasaray Istanbul in Dortmund, Germany, Tuesday, Nov.4, 2014 (Photo: AP)
European football's governing body UEFA on Thursday announced they have started an investigation into crowd trouble which marred Borussia Dortmund's Champions League win over Galatasaray.
Dortmund's 4-1 win on Tuesday had to be halted twice in the second-half after away fans hurled fireworks onto the pitch, then threw a firework into a block of home fans.
Both clubs are being investigated for crowd disturbances with Dortmund coming under scrutiny for failing to prevent the fireworks being thrown on the pitch and "a lack of organisation".
Galatasaray, who have already been fined 50,000 euros ($62,000) by UEFA after their fans lit flares in their defeat at Arsenal last month, now face heavier sanctions.
Dortmund police announced on Wednesday that two officers were injured, 21 fans were arrested and 700 people were being investigated for a range of charges from attempted manslaughter, breach of the peace and possession of explosives.
A total of 55 used fireworks were later found on the terraces in Dortmund and had been smuggled in by supporters despite strict security measures.
According to the German club, Turkish fans destroyed around 250 seats at their Westfalenstadion ground which will cost the club 30,000 euros to replace.
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