The comments from Hans-Georg Maassen, head of Germany's Federal Office for the Protection of the Constitution on Friday come after France's spy chief said Daesh is gearing up for a campaign of bomb attacks on large crowds in his country
France, where militants last year killed 130 people in coordinated assaults on cafes, bars, a football stadium and a music hall across Paris, will host Euro 2016, which starts on June 10 and runs for a month at 10 stadiums across the country.
"We know that Daesh has the European Championship in its sights," Maassen told the Rheinische Post newspaper, Daily Mirror reported.
He said that while there was no hard evidence of an attack being planned, there was "quite a lot of background noise, an elevated number of indications" that Daesh, al Qaeda or its Syrian affiliate Nusra Front wanted to perpetrate attacks against Western targets.
About 2.5 million spectators are expected for 51 games involving 24 teams at Euro 2016.