German police searched properties in several states to investigate hundreds of emails threatening bomb attacks against schools, train stations and other public places, the Federal Criminal Police Office said on Tuesday.
The raids in the states of North Rhine-Westphalia, Lower Saxony, Saxony-Anhalt and Hesse targeted four individuals, police and prosecutors said, including two juveniles.
The group is accused of "being responsible for hundreds of threatening emails with fake nationwide bomb threats against schools, main railway stations, shopping centres and other urban and public facilities."
In hundreds of the cases, the threatening emails triggered police security operations.
According to prosecutors, the aim of the emails was to "disturb the public peace by threatening to commit criminal offences ... to trigger the greatest possible number of police operations and to create the greatest possible uncertainty among the population."