Paris – French prosecutors on Thursday identified the second jihadist involved in the brutal killing of an elderly priest, as calls mounted for the prime minister and interior minister to resign after the latest terror attack.The prosecutor's office named the assailant as 19-year-old Abdel Malik Petitjean, who was listed in June on France's "Fiche S" of people posing a potential threat to national security after trying to reach Syria from Turkey.Petitjean, whose face was disfigured after being shot dead by police, had been harder to identify than his accomplice Adel Kermiche, also 19, and investigators confirmed his identity after a DNA match with his mother.The two jihadists were shown pledging allegiance to the Islamic State group in a video made before they stormed a church in the Normandy town of Saint-Étienne-du-Rouvray on Tuesday and slit the 86-year-old priest's throat at the altar.The attack came as the government was already facing a firestorm of criticism over alleged security failings after the Bastille Day truck massacre that left 84 people dead two weeks ago.'Government guilty'A brief show of political unity at a mass attended by different faiths in Paris on Wednesday quickly dissolved as Prime Minister Manuel Valls and Interior Minister Bernard Cazeneuve faced fresh calls to resign."If the government is not responsible for the wave of terrorism, it is guilty of not having done everything to stop it," Laurent Wauqiez, the deputy leader of the right-wing Republicans party, said in an interview with Le Figaro newspaper."Manuel Valls and Bernard Cazeneuve must go because they refuse to take vital measures to fight Islamism. We need a new government, determined to act."The French government has said that everything possible is being done to protect citizens, while warning that more terror attacks are inevitable, after three major strikes and several smaller attacks in the past 18 months.President Francois Hollande confirmed on Thursday the creation of a National Guard to be made up of reserve forces, after the government previously urged "patriots" to sign up to become reservists.Hollande said parliamentary consultations on the formation of the force would take place in September "so that this force can be created as fast as possible to protect the French".The government has faced tough questions as it emerged that both church attackers were on the radar of intelligence services, and had tried to go to Syria.Warnings of terror strikeOne of the criticisms is that Kermiche had been released from prison while awaiting trial on terror charges after his second attempt to travel to Syria. He was fitted with an electronic tag – allowing him out of the house on weekday mornings – despite calls from the prosecutor for him not to be released.Annie Geslin, who worked with Kermiche's mother for many years, told AFP "he was the youngest child and had psychological problems".Sources close to the investigation said Petitjean "strongly resembles" a man hunted by anti-terrorism police in the days before the church killing over fears he was about to carry out an act of terror.The sources said France's anti-terrorism police unit UCLAT sent out a note four days before the attack – saying it had received "reliable" information about a person "about to carry out an attack on national territory".Three members of Petitjean's family were taken into custody for questioning, said a source close to the investigation.In a video released by the ISIS news agency Amaq, the two men calling themselves by the noms de guerre Abu Omar and Abu Jalil al-Hanafi, hold hands as they swear "obedience" to ISIS leader Abu Bakr al-Baghdadi.Petitjean, from the Savoie region in eastern France, worked in several part-time sales jobs and was described by his incredulous mother as "gentle. He is not involved at all".Others who knew him were equally shocked, describing him as normal and showing no signs of radicalisation. "All the believers are shocked because he was known for his kindness. What was going on in his head?" asked Djamel Tazghat, who manages the local mosque.The attack is the third in two weeks in France and Germany in which jihadists have pledged allegiance to ISIS, increasing jitters in Europe over young, often unstable men being lured by the group's propaganda and calls to carry out attacks in their home countries.ISIS also claimed that Mohamed Lahouaiej Bouhlel, who ploughed a truck into a crowd in the French city of Nice on July 14, was one of their "soldiers". However, no direct link has been found.Security fears meant a march for the Nice victims planned on Sunday, as well as another in Saint-Étienne-du-Rouvray due to be held on Thursday, were cancelled.