A policeman who took the place of a hostage and was shot during a terror attack in France yesterday has died.

Arnaud Beltrame was left fighting for his life after being shot by Moroccan-born attacker Redouane Lakdim.

The 45-year-old police officer voluntarily swapped himself with a female hostage - and secretly left his phone on so his colleagues could hear what was going on inside.

Lakdim was shot dead after counter-terrorism officers stormed the supermarket in Trebes, southwest France.

Paying tribute to the police officer, interior minister Gerard Collomb tweeted: "Dead for his country. France will never forget his heroism, bravery and sacrifice."

Le lieutenant-colonel Arnaud Beltrame nous a quittés.
Mort pour la patrie.
Jamais la France n’oubliera son héroïsme, sa bravoure, son sacrifice.
Le coeur lourd, j’adresse le soutien du pays tout entier à sa famille, ses proches et ses compagnons de la @Gendarmerie de l’Aude. pic.twitter.com/I1h8eO7f9a

— Gérard Collomb (@gerardcollomb) March 24, 2018

Mr Beltrame's death takes the number of people killed to four - in addition to the gunman - and 15 others were injured.

Speaking to RTL radio this afternoon, Officer Beltrame’s brother Cedric said his sibling died a hero:

“He gave his life for someone else,” he said. “For a stranger - not even for someone from his family.”

 “He was very aware of what he was doing; he stayed professional using his phone.

“I think if we don’t describe him as a hero, I don’t know what you have to do to be a hero.”

Arrests

This morning, anti-terror police investigating the attack made a second arrest.

A 17-year-old suspect who knew the attacker has been detained. 

Separately, a woman he knew was held yesterday.

Attack

Lakdim, 25, had hijacked a car in the nearby city of Carcassonne - gravely wounding the driver and killing the passenger - before driving toward Trebes.

He shot at police officers before hiding in the supermarket, taking several people hostage.

During the resulting stand-off with police, Lakdim demanded the release of Salah Abdeslam - the only surviving member of the Islamic State cell that attacked Paris in 2015.

Lakdim killed two people before giving most of the hostages up, keeping one woman as a human shield, who Mr Beltrame traded places with.

Je salue l'engagement, le professionnalisme et le courage des forces de l'ordre. pic.twitter.com/wzINv0IM1p

— Emmanuel Macron (@EmmanuelMacron) March 23, 2018

President Emmanuel Macron had said of Mr Beltrame's actions: "He saved lives and honoured his colleagues and his country."

Mr Beltrame, who was married, had taken part in an exercise on dealing with a mass shooting in a supermarket as recently as December.

Lakdim, who was born in Morocco, was known to police, but only for "delinquent" crimes, like drug dealing.

He was on a watch list from 2014, according to France's prosecutor Francois Molins, but was not believed to be preparing any terrorist acts.

Shock

One neighbour told Le Parisien newspaper that the terrorist had dropped one of his little sisters off at school on Friday morning.

Another called him "calm" and "nice" and said he "always had a kind word to say."

Mr Collomb said: "We had monitored him and did not think he had been radicalised. He was already under surveillance when he suddenly decided to act."

The investigation will question how Lakdim was able to get a gun, and how and when he became radicalised.

#DGGN C'est avec une très vive émotion que je souhaite rendre solennellement hommage à l'héroïsme de notre camarade A.Beltrame décédé cette nuit. Je m'incline devant le courage, le sens du sacrifice et l'exemplarité de cet officier qui a donné sa vie pour la liberté des otages. pic.twitter.com/GnzmXWuFOX

— GendarmerieNationale (@Gendarmerie) March 24, 2018