Current EU president Slovakia beefed up security at several airports Friday following an unspecified threatening message, the interior ministry said, as Bratislava prepares for a major EU summit next month.
"Based on the threat, we have increased security measures at international airports in Bratislava, Poprad and Kosice," Interior Ministry spokesman Ivan Netik told AFP Friday, but refused to provide further details on character of the message.
"The National Safety and Analysis Center is currently analysing the information we received," Netik added.
The EU's 27 heads of state or government will meet September 16 in the capital Bratislava for an informal summit to chart the bloc's future without Britain after its voters decided to leave in a June referendum.
Slovakia, a eurozone member of 5.4 million currently holds the EU's rotating half-year presidency until January.