Local broadcaster Omroep West reported that a training session for ADO at its stadium nearby was halted while the grenade was removed. The graffiti appears to suggest involvement of somebody from Amsterdam. The Dutch capital's coat of arms features three Xs.
Amsterdam is home to Ajax, the Amsterdam club taking on Juventus on Wednesday in the Champions League quarterfinals. Jacco van Leeuwen, chairman of the ADO supporters' association, tells Omroep West "this is absolutely a new deep point in soccer history."
In February, vandals suspected of being soccer hooligans from The Hague painted graffiti including swastikas and anti-Semitic texts on buildings in Amsterdam ahead of a match between ADO and Ajax. Ajax is often portrayed as a club with historic links to Amsterdam's Jewish community.
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