Two suspects in last week's attack remain on the run, however.
They are Salah Abdeslam
, whose brother died in the attack, and Mohamed Abrini -- whom police named as a suspect Tuesday.
Police say Abrini -- now the subject of an international arrest warrant -- drove a car that was abandoned in the Paris neighborhood where one of the November 13 shootings occurred, according to police.
Cameras at a gas station in Resson, France -- on a highway between Brussels and Paris -- captured images of Abrini and Abdeslam two days before the attacks, the Belgian federal prosecutor's office said.
According to a source close to the investigation, Abrini went to Syria in 2014, but it was unclear when he returned to Europe. That would make him the latest of at least six of the alleged Paris attackers believed to have traveled to war-torn Syria.
Here's a look at some other developments:
France steps up ISIS fight
French warplanes struck eight targets Tuesday in the ISIS stronghold of Raqqa and new targets in Mosul, Iraq, Prime Minister Manuel Valls said in an address Wednesday to French lawmakers.
"This brings the number of attacks to more than 300 since the beginning of our involvement in the Levant," Valls said, referring to the region of the Middle East that includes Syria.
He vowed the country will further increase the volume of attacks, relying heavily on the aircraft carrier Charles de Gaulle to strike at targets in Iraq and Syria.
"There is no alternative. We have to destroy Daesh," he said, using another term for ISIS.
Belgium lockdown begins to ease
Brussels, which has been under partial lockdown since Friday night, is to remain at the highest terror alert level until at least the start of next week.
Much of the metro reopened Wednesday, though two lines remained closed.
Belgium, and specifically a Brussels suburb with a history of links to terrorism
, have been a focus of the investigation.
Sources in France close to the investigation believe Abdeslam could not have survived so long on the run without help, which might involve a support network in Belgium. They say extensive raids in Belgium on Sunday and Monday
-- in which 21 people were detained -- targeted people suspected of helping organize the attacks.
The suicide vest
A suicide vest
found in a garbage bin could give investigators new clues about Abdeslam's whereabouts. They are analyzing the vest, which was found in the Paris suburb of Montrouge, near where Abdeslam's cell phone was traced the night of the attacks, prosecutor Molins said.
Questions have been raised over whether Abdeslam aborted part of the attacks before fleeing toward Belgium. The Paris prosecutor suggested that could have been the case, noting that an ISIS message claiming responsibility for the attacks mentioned the 18th arrondissement, a Paris neighborhood where no attack occurred.
"Our investigation on that is still ongoing, to determine if Salah was planning on a suicide attack in the 18th arrondissement and why it didn't happen," Molins said.
But CNN terrorism analyst Paul Cruickshank asked why, if the suicide vest belonged to Abdeslam, would it have been discovered 10 days after the attacks?
"It is possible that somebody else may have jettisoned it, an attacker that we don't know much about at this point," Cruickshank said. "So they'll be doing all sorts of forensics, trying to establish who this belonged to, and that will be a huge priority for French investigators."
Authorities in Montrouge said garbage cans there are emptied "once or twice a week," Le Monde reported.
The global battle against ISIS
French President Francois Hollande is in the midst of a week of diplomacy aimed at building a global coalition to fight ISIS in Syria and Iraq.
He held talks Wednesday with German Chancellor Angela Merkel in Paris. The two visited the Place de la Republique, the site of a memorial to victims of the November 13 attacks, to lay flowers before their talks.
That meeting comes two days after Hollande hosted British Prime Minister David Cameron in Paris on Monday and met Tuesday with President Barack Obama in Washington.
Hollande travels Thursday to Moscow to see Russian President Vladimir Putin.
France and Britain are already part of a U.S.-led coalition that has been bombing ISIS targets. Russia is conducting separate airstrikes against ISIS and other groups in coordination with the forces of Syrian President Bashar al-Assad.
Any efforts to form an alliance that includes both Russia and the United States are likely to run into thorny issues such as Assad's future role in Syria and international sanctions against Russia for its interference in Ukraine.