Defense Minister Jean-Yves Le Drian said the nationwide deployment of troops would be completed by Tuesday and would focus on the most sensitive locations.
"The work on these attacks, on these terrorist and barbaric acts continues ... because we consider that there are most probably some possible accomplices," Valls told BFM television.
It was not clear exactly how many accomplices French forces were hunting for in addition to Hayat Boumeddiene, the widow of Amedy Coulibaly, the Islamic State group attacker who killed four hostages Friday at a kosher grocery in Paris before being killed by security forces.
But several others possible suspects appeared on their radar. French police have said the Charlie Hebdo attacks that left 12 dead were carried out by three people, but only two of those attackers — brothers Cherif and Said Kouachi — have been found.
In addition, video emerged Sunday of Coulibaly explaining how the attacks in Paris would unfold. French police want to find the person or persons who shot and posted the video, which was edited after the attacks that ended with Coulibaly being killed Friday.
Boumeddiene herself was seen traveling through Turkey with a male companion before reportedly arriving in Syria with him on Jan. 8 — the day after the Charlie Hebdo attack and the same day Coulibaly began his murderous spree by shooting dead a Paris policewoman.
Security camera video footage shown Monday by Turkey's Haberturk Television network showed Boumeddiene arriving at Istanbul's Sabiha Gokcen airport on Jan. 2 — five days before the first terror attack in Paris. A high ranking Turkish official, who spoke on condition of anonymity, confirmed that the woman on the video was Boumeddiene.
Turkish intelligence then tracked Boumeddiene from her arrival.
Turkish Foreign Minister Mevlut Cavusoglu told the state-run Anadolu Agency that she had stayed at a hotel in Istanbul with another person before crossing into Syria on Thursday. She and her traveling companion, a 23-year-old man, toured Istanbul, then left Jan. 4 for a town near the Turkish border, according to a Turkish intelligence official who was not authorized to speak on the record.
Her last phone signal was on Jan. 8 from the border town of Akcakale, where she crossed over apparently into Islamic State-controlled territory in Syria, the official said. Their Jan. 9 return plane tickets to Madrid went unused.
Survivors say the Charlie Hebdo attackers, two brothers from Paris, claimed they were being supported by al-Qaida in Yemen, the group the U.S. considers the most dangerous offshoot of that network. In his video and in comments to French media before he died, Coulibaly pledged allegiance to the Islamic State group, which has taken over large sections of Iraq and Syria.
Ties among the three attackers date back to at least 2005, when Coulibaly and Charlie Hebdo attacker Cherif Kouachi, 32, were jailed together. It later emerged that Cherif's older brother, 34-year-old Said, the other Charlie Hebdo gunman, fought with or was trained by al-Qaida in Yemen.
Cherif Kouachi was also convicted in 2008 along with several others of belonging to a network that sent jihadis to fight American forces in Iraq.
Israeli Prime Minister Benjamin Netanyahu on Monday visited the Paris kosher grocery where four of the hostages were killed Friday. Volunteers, meanwhile, recited prayers over the bodies of some hostage victims as they were prepared for burial by the Jewish Burial Society in Paris.