Transcript for Deadly 3-stage attack leaves the French countryside reeling

Overseas in France tonight. The frightening scene unfolding tonight. An ISIS "Gmgunman, and you will see the officer volunteering to switch places with the hostages. ABC's James Longman tonight from Paris. Reporter: Tonight, a three stage attack gripping the quiet French countryside. French police say 26-year-old redouane lakdim, hijacked a car in southern France, killing a passenger and seriously injuring the driver. Then, he opened fire at unarmed officers before driving to this supermarket. Around 50 people were inside when he charged in with a knife and gun reportedly shouting, I am a soldier of the islamic state. Reporter: He started to run after me and I managed to escape this man says. Lakdim killing two inside while requesting the release of the sole surviving suspect in the 2015 attacks in Paris that left 130 dead. With a hostage situation developing, this officer, Arnaud Beltrame, offering to swap himself for those inside. Keeping his cell line open, so that police knew when to storm in. And they did killing lakdim. The officer found wounded. Tonight, that officer now fighting for his life is being hailed a hero. David? James Longman, thank you.

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