Transcript for French police officer Arnaud Beltrame is being remembered as a hero

Overseas tonight, new developments in the deadly terror attack in France. The country paying tribute to a hero police lieutenant, killed after volunteering to trade places with hostages in a supermarket. Authorities revealing new details about the gunman supporting ISIS and weapons they recovered inside. Reporter: Bravery has a face don't in France. Lieutenant colonel being remembered for taking the place of a female hostage. The decorated Iraq war veteran walking inside this market, leaving his cell phone open when to storm in and kill the attacker. Now tributes for the 45-year-old killed by the gunman pouring in. His brother telling French media, he gave his life for a stranger. He probably knew he'd no chance. French officials calling him a hero who died for his nation. This, as police are learning more about the gunman redouane lakdim. ISIS material was found in his apartment. Three improvised explosives and a knife were found at the supermarket. He threatened to blow himself up at the supermarket after his rampage in southern France. Four people were killed in these attacks. They're interviewing an associate of lakdim. As France prepares for a day of tribute for their fallen officer.

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