Prosecutors said the men were held in a series of dawn raids in western and southern parts of the country. One of the 10 was confirmed as a Tajikistan national but officials disclosed few other details about the suspects. Local media reported they were ISIS sympathisers allegedly plotting a “serious, state-endangering crime”.
Prosecutors said the ten suspects were later released but confirmed investigations were continuing.
Germany has been the scene of several Islamist militant attacks in recent years, including a 2016 truck attack on a Berlin Christmas market that left 12 people dead.
Authorities across Europe are also on high alert for attacks from right-wing extremists after last week’s New Zealand mosque attack that left 50 dead.
Austrian police are investigating links between the attacker and the far-right Identitarian Movement, which opposes Muslim immigration.