German authorities have released two men who were arrested on suspicion that they may have been preparing a "serious act of violence," citing a lack of evidence.

The 46-year-old Iraqi and 29-year-old Nigerian were arrested on Thursday in Munich and nearby Fuerstenfeldbrueck following a tip to Bavarian security authorities. The daily Sueddeutsche Zeitung quoted Munich prosecutor Thomas Steinkraus-Koch Thursday evening as saying there had been indications the two were in contact with members of the Islamic State group.

However, the state criminal police office said that prosecutors ordered the men released on Friday after searches of their apartments turned up nothing incriminating. It said in a statement that questioning of the pair also failed to produce any further evidence.