French Interior Minister Gerald Darmanin said on Monday that there was a clear failure in the psychiatric care of the radicalized Islamist suffering from mental troubles who stabbed a German tourist to death in central Paris on the weekend, AFP reported.
"There was clearly a failure, not from the point of view of his monitoring by the intelligence services, but a psychiatric failure," Darmanin was quoted as having told BFM TV, adding the attacker had an "acute mental illness".
"Doctors said on several occasions that he was doing better, was more normal and could be free," he added.
Armand Rajabpour-Miyandoab, a French national of Iranian origin born in 1997, killed a 23-year-old German-Filipino man with two blows from a hammer and four from a knife on Saturday evening close to the Eiffel Tower.
The investigation is being handled by France anti-terror prosecutors who have launched a probe into a suspected terrorist plot.
France's top anti-terror prosecutor Jean-Francois Ricard said Sunday the man's mother had reported concerns about him as recently as October, but there was insufficient proof at the time to take legal action.
He had previously been arrested in 2016 for planning an attack, eventually serving four years in prison and under close watch following his release.
France has been hit by a number of attacks, the biggest one being the attack in November of 2015, claimed by the Islamic State (ISIS), in which 129 people were murdered.
The country has been under a heightened alert in recent years in the wake of the attacks.