German police conducted a series of raids throughout western Germany on Friday and Saturday as part of an anti-terrorism operation, prosecutors said on Saturday.

A total of 11 male suspects were arrested as part of the operation. All have since been released after no weapons or explosives were found.

What we know so far

Raids were carried out on Friday and Saturday in 10 cities across the western German state of North Rhine-Westphalia and one was conducted in Ulm in Baden-Württemberg.

Eleven male suspects aged between 22 and 35, mostly Tajikistan nationals, were detained as part of the operation.

At least six of the suspects are being investigated on suspicion of planning a "threatening act of violence against the state." Police suspect the six of being affiliated with the "Islamic State" (IS) extremist group.

Police were looking for weapons and explosives. When none were found, the 11 suspects were released.

Prosecutors said there is no indication yet of concrete targets or a concrete act of terrorism.

Suspected driving attack: Prosecutors said the raids were conducted after a 19-year-old Tajik man drove a car at excessive speed through a pedestrian zone in Essen. The man, an Essen resident, was stopped and arrested. Police are investigating the vehicle, which authorities said was an Opel Astra compact car. Prosecutors added they have yet to find a connection between the incident in Essen and the raids.

IS attacks in Europe: Countries in the European Union have been on high alert after multiple terror attacks in France, Belgium and Germany in recent years. In many cases, IS has claimed responsibility for the attacks.

dv/jlw (dpa, Reuters)

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