The Foreign Office today warned that stadiums, bars and fan zones showing the matches could be targets for terror attacks.
Fans were warned to be vigilant during the tournament in France, which is on alert after Europol warned there was a ‘high threat’ of an ISIS attack.
Scotland Yard also revealed today that it has seen ISIS propaganda and talk of plots during the tournament, and the threat level remains ‘severe’.
The news comes after a French terrorist planning 15 attacks during the Euros was arrested yesterday with a vast arsenal of weaponry – including 125kg of TNT and 5,000 rounds of ammo.
The right-wing nationalist Gregoire Moutaux also had two rocket launchers, five Kalashnikov assault rifles and more than 100 detonators when he was arrested on the Ukraine’s border with Poland.
A source close to the investigation said he was ‘armed to the teeth and ready to strike’.
The news came as French intelligence agencies said they were ‘deeply concerned’ about attacks from homegrown terrorists, after 16 Real Madrid fans were slaughtered in Iraq in May.