German authorities have released four suspected Islamists who were arrested ahead of the official festivities to mark the 21st anniversary of reunification.

They had been arrested on suspicion of planning an attack. Police announced Sunday that three men had been arrested near the western German city of Bonn, the former capital, where around 100,000 were expected to take part in German Unity Day celebrations attended by both Chancellor Angela Merkel and President Christian Wulff.

A further suspect had been taken into custody in Offenbach in the central state of Hesse.
Authorities had received information that the men, whom they described as being "from the Islamist scene," had illegally obtained weapons ahead of the events. But police found "no weapons or other dangerous objects" during their searches and later released him.

The four German-born men, three from Bonn and one from the town of Offenbach near Frankfurt am Main, were arrested Saturday afternoon, local broadcaster SWR said.

According to the initial reports, the men - aged between 22 and 27 - were attempting to acquire illegal weapons.
However, no weapons or dangerous objects were found in a search of their homes.

"There is neither evidence that the accused had links to terrorist groups nor that there were concrete preparations for an attack," said a spokesman for the Federal Prosecutions Office.

Authorities also said they did not know of any concrete threats to the festivities, which continued Monday October 3, the 21st anniversary of German reunification.