French police chiefs on Tuesday revealed they plan to step up security in Paris ahead of the Champions League clash between Paris Saint-Germain and Barcelona on Wednesday night.
The first leg of the quarter-final football match is expected to attract nearly 50,000 people to the Parc des Princes on the western fringes of Paris.
Thousands more will be following the tie in cafes and bars in and around the capital.
"The prefect of police prefect has considerably strengthened security resources," said French Interior Minister Gérald Darmanin during a visit to River Police officers on Tuesday.
"There has been a clear threat publicly mentioned by the Islamic State," Darmanin added.
Last month the group claimed responsibility for an attack at a concert hall just outside Moscow which left 144 people dead and hundreds injured.
Days after the assault, the French prime minister, Gabriel Attal, announced that France would raise its alert status to emergency - the highest level.
Work
"The Islamic State threatened the Champions League quarter-finals, not specifically in France, via one of its communication agencies, which disseminated messages on social networks," the French news agency AFP reported.
In one of the messages, a masked fighter with an assault rifle poses in front of photographs of the four stadiums in Madrid, London and Paris that will host the quarter-finals. "Kill them all", wrote the fighter.
Uefa, the governing body that organises the Champions League competition, said In a statement that it had been informed of the threats to the matches in its most prestigious tournament.
A spokesperson added that the games at the Santiago Bernabeu in Madrid and the Emirates Stadium in London would take place on Tuesday night.
PSG's tie and the fixture between Atletico Madrid and Borussia Dortmund on Wednesday night at the Wanda Metropolitana in Madrid would also proceed.
Review
Details of the heightened security in France emerged less than 24 hours before a committee of senior French politicians deliver their assessment on the country's readiness to host the Olympic and Paralympic Games this summer.
The Senate's Law Commission inquiry was prompted by the disastrous stewardship of the Champions League final in May 2022 between Liverpool and Real Madrid at the Stade de France in Saint Denis. Liverpool supporters narrowly avoided a fatal crush after they became hemmed in. Others were attacked and robbed by local criminals.
The commission's year-long investigation has focused on whether there will be enough police officers to deal with security threats effectively while respecting individual freedoms during the events which start on 26 July.
The senators have also scrutinised the transport plan for the Games. During 29 days of competition, nearly 16,000 athletes and 13.5 million spectators will be ferried between 37 Olympic and Paralympic venues in France and overseas.
"The Summer 2024 Olympic and Paralympic Games are events of unrivalled global proportions," said a spokesperson for the commission.
"The security arrangements put in place by the authorities will have to be beyond reproach and commensurate with the risks hanging over these Games."
(With newswires)