Story highlights Police intercept a delivery of illegal fireworks to right-wing extremists

Interior minister fears they could have been used to produce dangerous explosives

Nearly 90 police raid right-wing extremist group, detain 13, arrest 3

(CNN) When police in Germany intercepted a shipment of illegal fireworks, it prompted nearly 90 officers to swarm out in raids against right-wing radicals.

They detained 13 people on Wednesday, mostly in and around the southeastern town of Bamberg, and issued formal arrest warrants against three of them. They also confiscated a firearm and ammunition, other weapons and illegal Nazi propaganda and paraphernalia, police in the state of Bavaria said.

With extremist sentiments against asylum seekers at a peak, police suspected the "pyrotechnic devices," intended for delivery to the radicals, could have been used for the worst.

Thousands of weary refugees streaming in from perpetual war zones in the Middle East have received a warm welcome from most Germans, but radical groups have set fire to scores of refugee shelters.

"There could have been arson attacks planned against asylum seeker centers or similar places," Bavarian Interior Minister Joachim Herrmann told German public broadcaster ARD of the fireworks. He was afraid that the explosives in the large shipment could be combined into more dangerous bombs.

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