Ukrainian SBU agents detain a man at the Yahodyn border crossing on the Ukrainian-Polish border. (Ukraine's Intelligence Agency SBU Press Service via AP)

A French man apparently angered by the surge of Muslim migrants into Europe has been arrested trying to smuggle explosives and firearms for possible use in attacks during a major soccer tournament in France, officials in Ukraine said Monday.

The man, who was not immediately identified by Ukrainian officials, was arrested at a border crossing from Ukraine to Poland last month, said Vasily Hrytsak, chief of the Security Service of Ukraine, known as the SBU.

Ukraine’s intelligence agency said the man plotted the attacks as a “sign of protest” against the mass migration of foreigners into France and the growing number of Muslims living in the country. In the past year, more than 1 million asylum seekers have entered Europe from places including war-battered Syria and Iraq.

[Players on the field, soldiers at the Louvre]

Hrytsak described the suspect as motivated by “ultra-nationalist” views and said he had planned attacks against 15 targets, including a mosque, a synagogue and infrastructure in France during this month’s UEFA Euro 2016 soccer championship.

Ukraine’s intelligence agency said the man planned attacks against 15 targets in France, including a mosque, a synagogue and infrastructure, during this month’s UEFA Euro 2016 soccer championship. (TWP)

Security has been sharply increased for the soccer tournament, which will be held in stadiums across France.

The matches begin Friday at Paris’s Stade de France, where Islamic State militants detonated suicide bombs outside a soccer match on Nov. 13. A series of coordinated attacks that night across Paris claimed 130 lives.

Thousands of heavily armed soldiers will be deployed to provide security at popular tourist attractions and religious sites.

The arrest was first reported Saturday by the French TV network M6info, which identified the man only as Grégoire M., 25, and said he was from France’s Lorraine region.

On Monday, the SBU confirmed the arrest and released photographs and video of the man.

[The tip that led authorities to the Paris attack’s mastermind]

According to the Ukrainian security agency, the man had amassed five Kalashnikov rifles, more than 5,000 cartridges, two rocket-propelled grenades, more than 275 pounds of dynamite and 20 balaclavas.

Confiscated ammunition and explosives on a display at the Yahodyn border crossing on the Ukrainian-Polish border in Ukraine. (Ukraine's Intelligence Agency SBU Press Service via AP)

The agency said the suspect entered Ukraine in December, contacted armed groups fighting in southeastern Ukraine and sought to purchase weapons to bring back to France.

Hrytsak said the agency monitored the man as he purchased the weapons and then detained him as he attempted to leave Ukraine. He was arrested on terrorism, smuggling and weapons charges.

The UEFA Euro soccer tournament presents French authorities with a significant challenge. They must ensure security at sporting venues in 10 cities, as well as at train stations and other transportation hubs.

Security will be especially heavy at the “fan zone,” an enclosure of nearly 130,000 square yards at the base of the Eiffel Tower where fans can gather and watch the games for free on large screens.

Approximately 92,000 fans are expected to turn out in the fan zone, Jean-François Martins, who is in charge of tourism and sport for the French capital as an assistant to Paris Mayor Anne Hidalgo, said in an interview.

James McAuley in Paris contributed to this report.

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