Berlin: German Interior Minister Thomas de Maiziere was quoted on Saturday as saying there were "serious indications" of terror attacks in preparation in Europe and the United States but did not provide any further specific details.
De Maiziere, who until now has regularly played down security worries, told Bild am Sonntag newspaper that he was concerned.
"There are indications that have to be taken seriously of attacks in Europe and the United States," de Maiziere told the Sunday newspaper. "Events have prompted me to express my concerns publicly for the first time."
Over the past week, parcel bombs were sent from Yemen to US targets, and by militants in Greece to embassies and EU governments, including Chancellor Angela Merkel`s office.
De Maiziere called the parcel bombs sent from Yemen "a very serious attempted attack”.
Last month, the United States and Britain advised caution to travellers visiting Germany and France and intelligence sources spoke of plots against European cities involving al Qaeda and allied militants, some of them European citizens or residents.
But de Maiziere then said he saw no immediate signs of a threat, talking instead of a general abstract danger.
Germany has long viewed itself as a potential target because it has 4,590 military personnel stationed in Afghanistan, the third largest contingent of the 150,000-strong international force fighting the Taliban-led insurgency.
Germany has been largely spared terror attacks by Islamic militants, even though the leaders of the 9/11 attacks on the United States in 2001 were students based in Germany.
De Maiziere said this week Germany wants the EU to introduce new security measures against terror attacks on air freight to help tighten global rules.