The man who rammed his car into vehicles on a Berlin motorway in an alleged Islamist attack was driven by a "bizarre, religious mania," the public prosecutor in the German capital said on Thursday.
This was the conclusion of a psychiatric assessment of the suspect, said Martin Steltner, a spokesman for the prosecutor's office.
He would not rule out the possibility that the man may be waived of criminal culpability on the grounds of mental health.
The suspect, a 30-year-old Iraqi man who was living in Germany pending deportation after being refused asylum, has reportedly not yet spoken about the attack, which occurred on a stretch of highway near central Berlin on Tuesday evening.
The man is accused of deliberately crashing into vehicles on the city highway late Tuesday, targeting motorcyclists in particular.
Six people were injured, three of them seriously.
The suspect has been temporarily ordered into psychiatric care and is under investigation for attempted murder.
Investigators are treating the series of crashes as an Islamist attack, although prosecutors and police have also noted that there were "indications of mental instability."
"Not on the radar"
He had not been flagged to security authorities in the German capital prior to the rampage, an official said.
"He was not on the radar," a spokesman for the city's state interior department said, noting that the special police division for politically motivated crimes had no intelligence on the suspect.
The alleged attacker was on police records for previous crimes such as battery and resisting officers, however.
Berlin state interior minister Andreas Geisel explained to lawmakers on Thursday that the man had not been deported, despite his claim for asylum being rejected in 2017, because Germany has for years largely suspended the deportation of people to Iraq.
A firefighter who was seriously injured while travelling home from work on Tuesday remains in intensive care, one of his colleagues said.
"His condition is serious. We are thinking of him and wish him the best," a fire brigade spokesman said early Thursday.