LONDON — He was the youngest of the participants in the Paris terrorist attacks, a baby-faced 20-year-old whose attention had drifted from soccer, cigarettes and girls to the venomous messages of extremist Islam.

The man, Bilal Hadfi, a French citizen living in Brussels, went to Syria early this year to fight for the Islamic State. The government issued an arrest warrant for him, but then lost track of him. On Nov 13, Hadfi blew himself up outside the national soccer stadium on the northern outskirts of Paris, part of attacks that killed 130 people.

New details have emerged from teachers at his school about urgent warnings of Hadfi’s radicalisation, after he openly cheered the deadly January attack on the satirical newspaper Charlie Hebdo in Paris and posted extremist messages on Facebook.

Yesterday (Dec 26), the Belgian newspaper De Morgen reported that a police oversight body, known as Committee P, is investigating why the warnings were not passed on to authorities.

In an April 27 email, the school’s director, Mr Chris Pijpen, told an education official, Mr Charles Huygens, that Hadfi had not attended school since Feb 24. Officials met with his mother and aunt on March 23; they said he had left for Morocco, where he had relatives, because he was “fed up” with school.

But the school was rife with rumors that Hadfi had left for Syria, according to the email. It included images from Hadfi’s Facebook page, where he had adopted a nom de guerre, Abu Moudjahid al-Belgiki (the surname means “of Belgium”) and posed with a jihadi flag.

The email was reported by De Morgen, and then provided to The New York Times. Mr Huygens did not alert the police. “It’s true that the director told me by mail in April that our student had departed to Syria, but by then it was already too late,” Mr Huygens told De Morgen. Mr Pijpen said he did not contact the authorities himself because protocol required that he go through his superiors.

Belgian law requires that schools report suspicions of terrorist activity to authorities. In a phone interview yesterday, Mr Pijpen said he never got a reply to his email. “I expected that something would happen, some further action, at least someone from the administration that would come down to our school, or the police,” he said. “I was amazed that nothing happened. This was already after Charlie Hebdo and Verviers,” a Belgian town where the police in January killed two men suspected of links to a terrorist network plotting an attack.

“You would expect some reaction,” he added. “But then again, we’ve been asking for years for more support at our school, or the hiring of specialists, but never got any.”

As early as February 2014, according to a school report provided to The Times, officials said that Hadfi was having trouble at home in the Neder-over-Heembeek section of Brussels, where he lived with his mother and two brothers. He had been distraught after the death of his father a few years earlier, and a brother reported that Hadfi started smoking marijuana and skipping classes and that he would “hang out with the wrong friends”.

In a phone interview, another teacher at the school, Mr Kasmi M’Hamed, said that Hadfi began making alarming remarks early this year. He said the Charlie Hebdo employees who were killed deserved it because they had repeatedly been warned for insulting Islam. He also made homophobic remarks in class and said that the school’s emphasis on tolerance did not match his own beliefs.

A few days after the Paris attacks, Ms Sara Stacino, a former teacher of Hadfi’s, said in a phone interview that the school had prepared reports on Hadfi’s radicalisation, but that the reports were not passed on. She has left the school.

A short while later, Huygens suspended Pijpen, ostensibly for showing up late to a meeting. Mr Pijpen said he was being scapegoated for his superiors’ failure to act. “The administration wanted to cover this up so they can move on,” he said.

M’Hamed called for Mr Pijpen to be reinstated, calling him “a good director”.

Mr Frank Van de Vyver, a spokesman for the schoolteachers’ union, said in a phone interview that local officials were “looking for a scapegoat that would divert attention from the fact that they did nothing with the very sensitive information they got”. NEW YORK TIMES