THE HAGUE, Netherlands — Social media posts coupled with a lack of official information fueled the violence that followed a Maccabi Tel Aviv soccer match in Amsterdam last year, two inquiries into the events said in reports Monday.
Dozens were arrested and five people were treated in hospital in a series of violent overnight incidents following a November match between the Dutch team Ajax and Maccabi Tel Aviv.
''The events have left their mark on the city and led to fear, anger and sadness,'' Amsterdam Mayor Femke Halsema wrote in a letter to the city council presenting one of the reports.
Ahead of the game, pro-Palestinian demonstrators were banned by local authorities from gathering outside the stadium, and video showed a large crowd of Israeli fans chanting anti-Arab slogans on their way to the game. Afterward, youths on scooters and on foot crisscrossed the city in search of Israeli fans, punching and kicking them and then fleeing quickly to evade police.
The Rotterdam-based Institute for Safety and Crisis Management, tasked by the Amsterdam government to investigate the response to the violence, said the lack of official communication from the city allowed rumors on social media to flourish.
It noted that there was little to no official communication during the early hours of Nov. 8, in part because the situation was so unclear.
In a separate report, the inspectorate for the Justice Ministry concluded that the police were prepared for large-scale demonstrations, not the ''flash attacks'' perpetrated across the city and sparked by social media.
''Calls and images spread rapidly, reinforce existing tensions and can lead to group formation and confrontations on the street within a short period of time,'' the 57-page report found.
