MUNICH (Reuters) - Two men who were detained in Germany on suspicion of having links with Islamic State and of planning a "serious act of violence" have been released, Bavaria's office of criminal investigation said on Friday.
German police held the 46-year-old Iraqi and a 29-year-old Nigerian on Thursday after receiving a tip off. Security sources had provided information that both could have been in contact with members of the Islamic State militant group.
"During the course of comprehensive investigations, the criminal charge of planning a serious act of violent subversion could not yet be further corroborated or confirmed," Bavaria's criminal investigation office said in a statement.
It added that neither searches of the men's homes or rooms nor questioning had given any such clues.
It did not mention the possible Islamic State links in its statement.
Security in European countries has been intensified since attacks claimed by Islamic state that killed 31 people in Brussels in March and 130 in Paris in November.
Islamic State released a video on Tuesday suggesting it might carry out further attacks in the West, naming London, Berlin and Rome as possible targets.
(Reporting by Irene Preisinger; Writing by Michelle Martin; Editing by Toby Chopra)