According to the police, the detainees represented a network, which was in contact with Amri. One of the suspects was expected to help the attacker with getting fake identification documents so that he could hide out in Italy.
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The raids took place in Rome and its suburbs, as well as the cities of Naples, Matera, and Caserta.
In December 2016, a truck rammed into a crowd at a Christmas market in the center of Berlin. The attack left 12 people dead and almost 50 injured. The 24-year-old Amri was identified as the perpetrator and shot dead several days later by the Italian police in Milan.