A car and a motorcycle stand on the city motorway A100 after an accident in Berlin, Germany, Aug 19, 2020. The city's highway was still shut down after a series of traffic accidents that were allegedly all caused by one man. (PAUL ZINKEN / DPA VIA AP)

A 30-year-old man deliberately drove a car into other vehicles along a major Berlin highway, injuring six people in what German officials said on Wednesday appeared to be a deliberate attack motivated by Islamist ideology. They have now moved the perpetrator to a psychiatric unit.

The suspect's car collided with motorbikes and cars shortly before 7 pm and led to a complete closure of the highway, according to local reports

The public prosecutor's office said six people were injured, three seriously, when the Iraqi man allegedly drove into several vehicles along different parts of the A100 highway, one of the German capital's main traffic arteries.

The suspect's car collided with motorbikes and cars shortly before 7 pm and led to a complete closure of the highway, according to local reports.

German media reported that the man, driving a black Opel Astra, stopped on the highway and put a box on the roof of his car before claiming it contained explosives.

He was detained by police at the scene, and when specialists opened the box, they found only tools. Authorities have not revealed the man's name, as is customary in Germany.

Several German news outlets reported that the man shouted "Allahu akbar", an Arabic phrase meaning "God is great", as he got out of his car.

The Bild newspaper reported that he had shouted:"Nobody gets closer, or you will all die". Der Tagesspiegel reported that the suspect then rolled out a prayer carpet and started praying.

Berlin police and the public prosecutor's office said in a joint statement: "Comments made by the suspect after his criminal acts suggest a religious Islamist motivation.

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"According to the current state of our investigation, this was an Islamist-motivated attack," Germany's public prosecutor's office told the German news agency dpa.

The suspect is being investigated for attempted murder, and dangerous interference with traffic, according to authorities.

The prosecutor's statement also said there were indications that the suspect had psychological problems, adding that investigators have no evidence to believe that the suspect was a member of any terror group.

Authorities later ordered that the man be sent to a psychiatric institution temporarily, as the probe continued.

The man is already known to Berlin police, Der Tagesspiegel reported. He was born in Baghdad in 1990 and lived in a refugee home in Berlin.

He was detained in 2018 for injuring others and taken to a mental institution for a short time, according to the newspaper.

Berlin's senator for the interior, Andreas Geisel, told dpa: "A religiously motivated background cannot be excluded."

"The fact that the suspect was possibly suffering from psychological problems does not make this issue any easier," Geisel added.

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"If personal problems mix with religiously loaded ideas, this can lead to uncontrollable acts－yesterday's events have shown in a very painful way how vulnerable our society is."