At least one of the attackers outside France’s national soccer stadium had a ticket to the game and attempted to enter the 80,000-person venue, according to a Stade de France security guard who was on duty and French police.

The guard—who asked to be identified only by his first name, Zouheir—said the attacker was discovered wearing an explosives vest when he was frisked at the entrance to the stadium about 15 minutes into the game. France was playing an exhibition against Germany inside.

While attempting to back away from security, Zouheir said, the attacker detonated the vest, which was loaded with explosives and bolts, according to Paris prosecutor François Molins. Zouheir, who was stationed by the players’ tunnel, said he was briefed on the sequence by the security frisking team at the gate.

A police officer confirmed the sequence, adding that police suspect the attacker aimed to detonate his vest inside the stadium in order to provoke a deadly stampede.

The account sheds light on why the suicide attacks on Stade de France failed to cause the carnage that occurred at the Bataclan concert hall and restaurants across Paris. More than 120 people died in the string of attacks Friday.

The blasts occurred during the first half of the game, sowing confusion throughout the stadium. At least two blasts were heard clearly inside the stadium, witnesses said, and on the television broadcast. Loud blasts aren’t uncommon at soccer matches on the European continent where fans sometimes set off firecrackers.

At first, Zouheir said he too thought the early blast was a firecracker. Then his walkie-talkie came alive with chatter, and he noticed that French President Francois Hollande—who was in attendance at the Stade de France—was being ushered out of the stadium.

“Once I saw Hollande being evacuated, I knew it wasn’t firecrackers,” said Zouheir, who could see the VIP box from his post. He added that President Hollande left after the first blast.

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