Three days before the start of the 2024 Olympics, France's interior minister said about 1,000 people suspected of possibly meddling for a foreign power have been blocked from attending the Olympics — one of the security challenges that Paris is cracking down on in its goal to keep Games safe for athletes and fans.

About 1 million background checks have scrutinized Olympic volunteers, workers and others involved in the Games as well as those applying for passes to enter the most tightly controlled security zone in Paris — along the banks of the Seine — ahead of the opening ceremony on the river Friday.

The checks blocked about 5,000 people from attending, Interior Minister Gerald Darmanin said Tuesday. Out of them, "there are 1,000 people whom we suspect of foreign interference — we can say spying," Darmanin said.

Darmanin, who is staying on in a caretaker role until a new government is formed following legislative elections this month that denied President Emmanuel Macron's centrist coalition a majority, has repeatedly pointed to suspicions of Russia-backed interference.

"We're here to make sure ... that sport isn't used for spying, for cyberattacks or to criticize and sometimes even lie about France and the French," Darmanin said.

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He added that "interfering and manipulating information" is not coming from Russia only but from some other countries, too, which he did not name. He also didn't give more information on the suspected meddling.

"That's why we're on the alert, and we want them to know that we're not naive," he said.

Others blocked from the Olympics after background checks were flagged for suspected Islamic radicalization, left- or right-wing political extremism, significant criminal records and other security concerns, Darmanin said.

"These people, we didn't think it was a good idea for them to be stadium stewards, volunteers or that they accompany [sports] teams. Out of 1 million people, 5,000 is not a lot, and it shows the deep work of the Interior ministry," he said.

Paris deploys thousands of police

Paris is deploying 35,000 police officers each day for the Olympics, which run Friday to Aug. 11, with a peak of 45,000 for the opening ceremony. In addition, 10,000 soldiers are taking part in security operations in the Paris region.

France also is getting help from more than 40 countries that together have sent at least 1,900 police reinforcements.

"Of course, we're particularly protective of the Ukrainian team, which is obviously under considerable threat," Darmanin said.

The interior minister had previously said Israeli athletes would be protected 24 hours a day by elite police unit GIGN, which is in charge of counterterrorism and the protection of government officials, among other things.

In a handwritten note to them, Darmanin said "the largest global event that a country can organize" is "finally" here after four years of preparation but noted the unprecedented security challenges.

"Your task will not be easy," Darmanin said in the letter posted on the social platform X late Monday. Paris has repeatedly suffered deadly extremist attacks, and international tensions are high because of the wars in Ukraine and Gaza.

Olympic organizers also have cyberattack concerns, while rights campaigners and Games critics are worried about Paris' use of AI-equipped surveillance technology and the broad scope and scale of Olympic security that they fear may remain in place beyond the Olympics.

Rather than build an Olympic park with venues grouped together outside of the city centre, like Rio de Janeiro in 2016 or London in 2012, Paris has chosen to host many of the events in the heart of the bustling capital of 2 million inhabitants, with others dotted around suburbs that house millions more.

Putting temporary sports arenas in public spaces and staging the opening ceremony along the Seine makes those protections more complex.