A 24-year-old Muslim immigrant from Mali was hailed Sunday as a hero for saving the lives of as many as 15 people trapped in a kosher supermarket in Paris where a gunman killed four hostages Friday. Lassana Bathily said he hid the captives in a freezer in the basement.

"When they came out they congratulated me. They told me, 'Thank you, really.' I said, 'It's nothing. That's life,'" the Daily Telegraph quoted Bathily as saying.

Bathily told BFM TV, France, he lifted a trap door in the floor after he saw Amedy Coulibaly start shooting hostages at the Hyper Cacher supermarket in Porte de Vincennes, Paris, and ushered the customers inside a freezer. He then turned off the light and the freezer, told them to remain calm, shut the freezer and went went out, le Parisien reported.

Bathily managed to get out of the store by using a dumbwaiter that led to the street and told police what was happening inside, al-Bawaba reported. Police initially treated him as a possible assailant and ordered him to the ground, hands over his head. "They cuffed me and held me for an hour and a half as if I was with them," Bathily said.

Johan Dorre, 36, one of those in the freezer managed to place a cell phone call to an uncle and told him they were trapped in the sub-basement.

Bathily is credited with saving at least six people including a baby, Councillor Malik Yettou said, but BFM TV put the number at 15.

L'Express reported a second employee escaped through an emergency exit and gave the store keys to police.

Friday's incident intensified the fears of Jews in France, 7,000 of whom have fled the country in recent years. Israel News Feed reported hundreds showed up at an informational session in Paris Sunday on emigrating to Israel.

The incident was one of two terrorist attacks in Paris last week. The other was the massacre at the Charlie Hebdo offices that left 12 people dead. Both Coulibaly and the brothers involved in the Charlie Hebdo shooting were killed by police. Coulibaly had vowed to hold the hostages until police released Said and Chérif Kouachi, the suspected Charlie Hebdo shooters. They were holed up in a Paris warehouse.