French authorities have detained a man linked to an Algerian driver who sped his car into a group of soldiers near Paris. It is the first arrest in the case.

A judicial official said Thursday the man was arrested Wednesday and will be questioned by counterterrorism investigators.

Police have been unable to question the chief suspect, Hamou Benlatreche, because he remains hospitalized with serious injuries sustained during his arrest, according to the official. The official was not authorized to be publicly named while speaking about an ongoing investigation.

Police have not disclosed a motive for the Aug. 9 attack that injured six soldiers in the Paris suburb of Levallois-Perret.

Police say Benlatreche, 37, was known to authorities as a suspect in minor crimes but not as someone with radical beliefs.