The 23-year-old, suspected of being an accomplice to Cheurfi, was arrested in the Seine-et-Marne region east of Paris on Monday, judicial sources said on Tuesday.
Responsibility for the attack, in which police officer Xavier Jugelé was killed just before last month's French presidential election first round, was claimed by the Islamic State armed group (IS).
Although a declaration of allegiance to IS was found near Cheurfi's body, the organisation's claim has puzzled investigators since the IS statement named a certain "Abou Youssef the Belgian", a description that does not fit the actual assailant.
A pump-action shotgun, two larges knives and munitions were found in his car.
Algerian charged over Thalys, Paris attacks
An Algerian national was charged with complicity with terrorist murder and implication in a terror plot on 21 April, sources revealed on Tuesday.
Bilal Chatra is accused of helping Ayoub El Khazzani, who seriously wounded one passenger when he opened fire aboard a Thalys train between Amsterdam and Paris on 21 August 2015, and Abdelhamid Abaaoud, who is believed to be one of the coordinators on the November 2015 Paris attacks.
He was arrested in Germany in July last year and handed over to the French authorities in response to an international arrest warrant relating to the Thalys attack.
The German authorities believe Chatra checked out access to Europe via the Balkans for Abaaoud in 2015.