Six Syrian asylum seekers were released on Wednesday, a day after they were detained in a major anti-terror operation that involved around 500 police officers in four German cities.

The men were suspected of "planning an attack with weapons or explosives on a public target in Germany," German prosecutors said on Tuesday. Other refugees tipped off investigators about the group, who were reportedly active as "Islamic State" (IS) fighters in Syria, reported Welt, citing sources close to the investigation.

On Wednesday, however, investigators said there was not enough evidence to keep the suspects in jail.

"There is no pressing evidence of the preparation of an attack or IS membership," a spokesman for the prosecutors said.

The police searched eight apartments in Kassel, Hanover, Essen and Leipzig, but found no weapons or explosives. The seized laptops, tablets, and cell phones also failed to turn up material against the detainees.

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'References' to Islamic State found

The six men, aged between 20 and 28, were "cooperative" while talking to the police and provided the required information, according to the prosecutors. They also denied allegations against them.

Despite not finding evidence of actual IS membership, officials discovered "references" to the jihadist militia and information suggesting that the group may have considered scenarios for terror attacks.

"We are still evaluating the data," German prosecutors said.

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Four of the men entered Germany in December 2014 and the remaining two requested asylum in the summer of 2015.

Immediately after the arrests, German media said the suspects were planning an attack at a Christmas market in the western city of Essen. The unconfirmed plot echoes the deadly Berlin attack last year,when a Tunisian man drove a truck into a Christmas market and killed 12 people.

Germany's biggest Islamist trials Failed Bonn bomb The blue bag left on the platform at Bonn's central station in 2012 contained explosives that did not go off, but a city-wide manhunt unfolded. Marco G. was eventually arrested and charged with planting the bomb. Three others are charged with plotting to assassinate a politician from the far-right PRO-NRW party. Their group allegedly drew inspration from an Islamist movement in Uzbekistan.

Germany's biggest Islamist trials Frankfurt airport bus attack In March 2011, Arid Uka shot dead two US servicemen waiting for a bus at Frankfurt airport prior to deployment in Afghanistan. "This is indeed the first Islamic-motivated terror strike to have happened in Germany," the judge said, adding Uka had sought revenge for military operations in Afghanistan. Uka, born in Kosovo, acted alone and was sentenced to life in prison in February 2012.

Germany's biggest Islamist trials The Sauerland Cell The "Sauerland Cell" was a German cell of the Islamic Jihad Union (IJU), a terrorist group on the Pakistani-Afghan border. The four German and Turkish men had planned large-scale bomb attacks against American targets in Germany from their base in the western region of the Sauerland. Arrested in September 2007, they were sentenced in March 2010 for up to 12 years.

Germany's biggest Islamist trials Sharia Police Sven Lau, a Salafist Muslim, was the man behind a well-known Islamist publicity stunt. In 2014, Lau led several men around the city of Wuppertal in orange security vests labeled "Sharia police." Acting as state authorities, they warned people visiting local clubs and bars to adhere to Sharia, or Islamic law. He is currently on trial for backing a terror group fighting in Syria.

Germany's biggest Islamist trials Big mouth Nils D., a Salafist from Dinslaken, joined the "Islamic State" in Syria in October 2013. He tracked down the group's deserters - armed with explosives and guns. He returned to Germany a year later, and boastful statements about his time in Syria eventually got him arrested. He confessed the names of other German Islamic extremists and was sentenced to four-and-a-half years in jail.

Germany's biggest Islamist trials "Biggest mistake of my life" On the final day of Harry S.'s July 2016 trial, he said "going to Syria was the biggest mistake of my life." The Bremen-born Muslim convert spent three months with "Islamic State" in Syria in 2015. He wanted out after civilians were murdered for a short recruitment film he helped make. He was sentenced to three years in jail for being part of a foreign terrorist organization.



dj/rt (AFP, dpa)