A video released by ISIL fighters purportedly showing them burning their French passports has provoked much discussion in the French media.

On Wednesday, French authorities named a second Frenchman in a video showing the killing of Syrian prisoners as 22-year-old Mickael Dos Santos.

Terrorism expert Jean-Charles Brisard said: “He’s a convert, we know that he has been in that area for a long time, for a year and a half, since August 2013. He learned how to use arms, he became ultra-radical and we also know that he is extremely violent. We can see it through what he posted on the social networks: he mentions the threat of terrorist attacks against France, he calls for jihad, and he often mentions Mohamed Merah’s name.”

Dos Santos, who was of Portuguese origin but born in France, was a recent convert to Islam.

In the Paris suburb of Champigny-sur-Marne where he lived, locals said they were shocked and that his behaviour was against Islamic teachings.

One man said: “I never imagined he would be capable of doing things like that.”

“For us he is a murderer, because that’s not Islam, Islam is peace,” added another.

About 1,000 French jihadists are thought to have gone to Syria and Iraq.