French officials have confirmed the identity of the second Normandy knife attacker as 19-year-old Abdel Malik Nabil Petitjean. The teenager appeared in a video pledging allegiance to the Islamic State (Isis/Daesh) alongside fellow extremist Adel Kermiche prior to the assault on the Saint-Etienne parish church in Normandy.

AFP reported that Petitjean – like Kermiche – had been on a list of extremists under observation by French security services before the pair were able to storm the Catholic church just south of Rouen on 26 July.

Five people were initially taken hostage by the pair before police intervened. They cut the throat of priest Father Jacques Hamel in front of the small congregation before the killers were shot dead by armed security services.

Petitjean's identify had already been released by IS which published an online video the Normandy attackers had made pledging allegiance to the terror group. He was referred to in the footage simply as Abdel Malik P.

That the second attacker was also known to authorities will intensify criticism of the French intelligence services. It emerged that Kermiche was known not only to have close links with IS operatives both at home and abroad and had attempted to travel to Syria but that he was also wearing an electronic monitoring device during the recent attack.

Kermiche had served part of a sentence for various terrorist offences. On one occasion he was halted in Munich, with German police sending him back to France, then he was stopped in Turkey. French judges heard how he was suffering with deep depression and "other mental problems".

The judge who freed Kermiche said he was "aware of his mistakes", and was a good candidate to be reintegrated back into society. As part of his parole conditions, he was allowed out for a four-hour period unmonitored from 8.30am each day, according to psychological reports leaked to Le Monde.

isis amaq normandy
Killers Adel Kermiche (L) and Abdel Malik Nabil Petitjean (R) appear in a video released by IS