German police arrested three suspected Daesh/ISIS members on Tuesday on suspicion of planning a terrorist attack.

Nadja Niesen, spokeswoman at the Frankfurt state prosecutor’s office, said the suspects, who were arrested in Offenbach, were planning an attack in the Rhine-Main metropolitan region with firearms or explosives.

She said the prime suspect, a 24-year-old German of Macedonian origin, had already purchased material to build explosive devices.

Two other suspects, age 22 and 21, were Turkish citizens.

Niesen said police seized documents and external hard disks during raids on properties associated with the suspects.

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