German authorities have conducted 13 counterterrorism raids in five federal states, police in the eastern state of Thuringia said Tuesday.
The location of the raids included 12 apartments and one shared accommodation in the states of Thuringia, Hamburg, North Rhine-Westphalia, Saxony and Bavaria, police said.
Germany has been on high alert since two extremist attacks were carried out in the space of one week in July. Both were claimed by Daesh.
Earlier this month, a Syrian man detained on suspicion of plotting to attack a Berlin airport was found dead in his prison cell.