The suspect was arrested in the Uckermark, a district in Brandenburg, the state's interior minister Karl Heinz Schröter has announced.
Further details remain unknown at this stage, including the specifics of the alleged plot.
Germany suffered multiple attacks in 2016.
Syrian held in Germany over Berlin suicide attack plan
30 May 2017
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German police have arrested a 17-year-old Syrian suspected of planning a suicide attack in Berlin, officials say.
