Salah Abdeslam, brother of Brahim Abdeslam, who blew himself up in a Paris cafe on Friday, was stopped by Austrian police on September 9th as he travelled into the federal state of Upper Austria from Germany, an Interior Ministry spokesman told broadcaster ORF.
Abdeslam's name was on rental documents relating to a Belgian Volkswagen Polo used by the Paris attackers, making him a priority for French and European security services in the wake of the mass killings.
Police swarmed through Strasbourg in search of Abdeslam on Monday after a tip-off but failed to find him.
The 26-year old was involved in a traffic stop just after he entered Austria and identified himself correctly to police as a French citizen.
The Interior Ministry spokesman said police had no indication at the time that Abdeslam or the two men in the car with him were linked to jihadism.
The three were allowed to continue their journey and headed for Vienna, saying that they planned a few days' holiday in Austria, Interior Minister Johanna Mikl-Leitner told ÖRF.