Beltrame offered to exchange himself for one of the female hostages held inside the Super U supermarket during the attack, and was shot while entering the supermarket.
When he went inside the supermarket, he left his phone on so police could hear his interactions with the gunman, Collomb said.
As soon as they heard gunfire, police went in and killed the gunman.
Beltrame died Friday night, police said.
"I bow to the courage, the sense of sacrifice and the exemplary nature of this officer who gave his life for the freedom of the hostages," the French National Police tweeted.
Married with no children, Beltrame had had a stellar career in the French military police and had already received a number of awards for bravery.
He served in Iraq in 2005, and was given an award for bravery in 2007, Macron said. For four years he was a commander in the Republican Guard, which provides security at the Elysee Palace, home of the President.
In 2012 he was knighted in France's prestigious Legion of Honor. In his illustrious career, Beltrame had also served as secretary general in the Ecology Ministry for four years.
Beltrame was appointed deputy-commander of the anti-terror police in the Aude region last year.
According to the French newspaper La Depeche du Midi, last December Beltrame led a simulated terror attack on a supermarket for training purposes, very similar to the one on Friday where he lost his life.
"His leadership skills, his willingness, his unfailing commitment were appreciated by everyone, especially in the development of counter-terrorism capacity in the Aude police force," Macron said.
"Lieutenant Colonel Arnaud Beltrame died in the service of the nation to which he had already contributed so much. By giving his life to end the murderous escapade of a jihadist terrorist, he died a hero."
