Germany has been put on increased security alert through fears of a heightened threat from international terrorism.
The move followed new intelligence, said Thomas de Maiziere, the country's top security official. Germans will see a visible response to the threat, including more police at airports and railway stations.
Mr de Maiziere urged calm, saying: "There is reason for worry, but there is no reason for hysteria," he said. "We will not allow international terror to limit us in our way of life and our culture of freedom," according to The Press Association.
According to Maiziere, the German government had been apprised of terrorist designs in the wake of the "parcel bomb incident" in which explosives hidden inside printer cartridges were sent as air cargo from Yemen to synagogues in the US city of Boston.
However, timely action by airport staff in Dubai and the UK helped detect the explosives which British experts said were designed to explode over the US East Coast, RTT News reports.