FRANKFURT AM MAIN - German prosecutors on Tuesday were probing whether a "terrorist" motive led a man to hijack an articulated lorry and smash it into cars stopped at a traffic light in the city of Limburg, injuring several people.

Media outlets identified the driver as a Syrian asylum seeker in his early 30s who arrived with the massive migrant influx to Germany in 2015.

Public broadcaster ZDF quoted security authorities as saying they believed the incident had a "terrorist backdrop", but the prosecutor's office in Frankfurt declined to confirm this.

Germany has been on alert following several jihadist attacks in recent years claimed by the Islamic State group.

The most deadly was committed in 2016 by a 23-year-old Tunisian, who killed 12 people when he stole a truck and plowed it through a Berlin Christmas market.

The authorities remained cautious.

"There is still no confirmed information -- we are still in the critical phase of the investigation," a spokesman at the Frankfurt prosecutor told AFP.

He declined to confirm whether the suspect was Syrian.

A spokesman for the federal prosecutor's office in Karlsruhe, which usually takes over terror probes, said it was for now leaving the case to Frankfurt.

The white articulated lorry slammed into around nine cars at the red light opposite the Limburg courthouse in western Hesse state late Monday afternoon, crushing them together.

Police said "around nine people were slightly injured," including the driver of the stolen vehicle, who was immediately taken into custody.

News agency DPA citing security sources said the suspect was known to the police for drug offenses and grievous bodily harm but had no apparent links to the Islamist scene. Police searched his home in the nearby town of Langen overnight.

The original driver of the truck, who was not named, was quoted by daily Frankfurter Neue Presse (FNP) as saying a man had "dragged" him out of his lorry.

He said the man, with short dark hair and a full beard, had yanked open the driver-side door and stared at him wide-eyed before forcing him out of the vehicle.

"I asked him 'What do you want from me?'," he told FNP. "He didn't say a word."

The truck sped into the parked cars a few hundred meters away and came to a stop on the central reservation of a six-lane road. -AFP