“I am thinking about the family of the butcher, about the customer who died for nothing, and about the colonel who sacrificed himself for us and that, had he not done that, he would be among us,” she said in an interview on Tuesday.
The attack on Friday morning killed four people and left four others seriously wounded. The attacker, Radouane Lakdim, 25, who was killed by the police, was a French-Moroccan of dual citizenship, who came to France when he was 4 months old.
While French officials believed he had been radicalized in part because of his association with local Salafists, followers of an ultraconservative branch of Islam, and had put him on an active watch list, Mr. Lakdim was not thought to be on the verge of violence, said François Molins, the prosecutor, in a briefing late Monday.
Mr. Lakdim did not seem to harbor any desires of going to Syria or Iraq, Mr. Molins added. Like a number of others who have drifted into terrorist behavior, Mr. Lakdim had a history as a petty criminal and small-time drug trafficker, and he had served time in prison. The French domestic intelligence agency had recently summoned Mr. Lakdim for an interview, but he had not yet gone to it.
Accounts from witnesses show how quickly a familiar place can be transformed into a hostile one.
At 10:39 on Friday morning, more than two dozen people were doing their weekly shopping in the Super U in Trèbes, a town of about 5,500, in the Aude Department in southern France when Mr. Lakdim arrived in the parking lot in a stolen car. He had stolen it about an hour earlier after wounding the driver and fatally shooting a passenger, Jean Mazières.
Mr. Lakdim ran toward the supermarket brandishing a handgun and a large knife and began shooting almost as soon as he got inside, killing a butcher, Christian Medves, 50. He ran down a row of cash registers, shouting: “Allahu akbar” and, using the Arabic acronym for the Islamic State, “I am a soldier of Daesh.” The Islamic State later claimed responsibility for the attack, using wording that suggested that the attacker was inspired by the group, rather than directed by it.
“Get down, get down, don’t move” Mr. Lakdim said, fatally shooting a customer at almost the same time.
The customer, Hervé Sosna, 65, was a retired mason, said Denis Vial, a retiree who was in same checkout line and dropped to the floor next to him, according to a video interview published in the local paper, La Depêche du Midi.
Ms. Perderiset ignored the gunman’s instructions to get down. She pushed away her shopping cart and ran toward the back of the store, arriving at the fish counter. “I saw myself arrive alone in front of the woman who works behind the fish counter and she gestured me to come hide in the reserve room for the fish,” Ms. Perderiset said.
Mr. Vial, meanwhile, was lying still on the floor as were about a dozen other employees and shoppers, he said. They were there for nearly an hour when Colonel Beltrame, 44, entered unarmed, holding his hands in the air and talking to Mr. Lakdim, who was holding one of the cashiers as a shield with a gun pointed to her head, said the prosecutor, Mr. Molins.
For most people it would be unimaginable to approach, unarmed, a gunman, said Bernard Bajolet, the former head of the French foreign intelligence service, but Colonel Beltrame was not just brave, he was also deeply prepared for the moment.
In 2005, when Mr. Bajolet was serving as ambassador to Iraq, Colonel Beltrame led the gendarmes contingent guarding him.
The French gendarmes sent to protect overseas operations are given especially tough training, Mr. Bajolet said, but Colonel Beltrame stood out. Then a captain, “he said how enthusiastic he was about the mission and that he was ready to sacrifice for it — not in a suicidal sense, but he knew that in certain circumstances you have to do certain things and he told me that,” Mr. Bajolet said.
“He was a man with a perfect sense of control,” Mr. Bajolet added. “I trusted him completely.”
Daniel Cerdan, also a former member of the gendarmerie’s elite unit, said Colonel Beltrame would have planned his approach carefully.
“When he took that women’s place, he did so because he wanted to save a human life,” Mr. Cerdan said in an interview, noting that Colonel Beltrame might have perceived Mr. Lakdim’s willingness to speak with him as an opening.
“I don’t think that in his mind it was a sacrifice,” Mr. Cerdan said. “It was thought out.”
Mr. Vial and others described hearing Colonel Beltrame say calmly to Mr. Lakdim, as he held the female cashier hostage, “Free her, she has done nothing.”
Mr. Lakdim did so a few minutes later, and demanded that Salah Abdeslam, the only surviving member of the Islamic State group that killed 130 people in and around Paris in a series of coordinated attacks in November 2015, be freed. Colonel Beltrame told him he would convey the message, according to the prosecutor, Mr. Molins.
What happened next was not so clear. Gunshots were heard over the line that Colonel Beltrame had left open on his cellphone, and gendarmes, fearing that their comrade was under attack, began the assault that ultimately killed Mr. Lakdim.
An autopsy found that while Colonel Beltrame had a gunshot wound in one arm and a foot, the lethal blow came from a knife wound in the neck.