A French police officer who traded places with a hostage Friday during a supermarket siege died of his injuries on Saturday, becoming the fourth victim of the attack in Trebes. French President Emmanuel Macron led tributes to the fallen police officer, Lieutenant-Colonel Arnaud Beltrame, saying he “died a hero” and deserves “the respect and admiration of the whole nation.” Beltrame, who surrendered his weapon and voluntarily offered himself to the attacker in exchange for the release of a female hostage, was shot and stabbed before the siege ended. He “displayed exceptional calm in the heat of the moment and showed the virtue of our security forces in astonishing fashion,” Macron said. Flags were flown at half-mast Saturday at gendarmerie bases throughout the country to honor Beltrame. The attacker, identified as Moroccan-born Radouane Lakdim, 25, was also killed in the siege, which came after Lakdim allegedly went on a shooting spree in Carcassonne.