Mistakes happen in many investigations, but it appears the Berlin terrorist attack with a hijacked lorry was far worse. Here is one passage:Link:https://www.thelocal.de/20171012/off...error-attackerThe special investigator found that, although Berlin police considered Amri to be the most dangerous Islamist in the city, they only put him under surveillance for a few weeks. Even then, the monitoring stopped on weekends and on public holidays.
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