In your case it was easier because the perpetrator was known. With griefers it is more complicated but not impossible. If the perpetrators do not stop, the national and international authorities must be called in. Griefers have an advantage; they think they are safe and so the State Criminal Police Office, FBI, LKA, BDI, Interpool and Europool have leads and if the perpetrator is caught, he or she will go to prison for a long, long time.
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