The Paris prosecutor has said the fate of the suspected organiser of Friday's attacks remains unknown after a police raid on a flat ended in bloodshed.
Francois Molins told reporters Abdelhamid Abaaoud was not among eight people arrested during the raid in the Paris suburb of Saint Denis.
However, human remains found in the rubble of the flat had still to be identified, he said.
A woman blew herself up and another suspect was shot dead during the raid.
The building was so badly damaged that it is unclear if there is a third body in the rubble, an interior ministry spokesman said.
Abaaoud is said to have organised Friday's gun and bomb attacks in Paris, when 129 people were killed.
All of the victims of the attacks - which targeted a concert hall, cafes and the Stade de France stadium and were claimed by the so-called Islamic State (IS) group - have now been identified, the government says.
Molins said the police operation in Saint Denis had foiled a new attack, stopping a "new terrorist cell" that appeared to be ready to strike.
"At this time, I'm not in a position to give a precise and definitive number for the people who died, nor their identities, but there are at least two dead people," he added.
Details he gave of the operation in Saint Denis paint a picture of a ferocious battle
Police used 5,000 rounds of ammunition
The main building targeted was hit so hard it is now at risk of collapse
A body was found "riddled with impacts", which made it impossible to identify for now
Seven men and one woman were arrested
However, Salah Abdeslam, a 26-year-old French national identified as a suspect in Friday's attacks, was not among them, he said - nor was Abdelhamid Abaaoud.
Also on Wednesday, a teacher at a Jewish school in the southern city of Marseille was stabbed by three men. Police say his life is not in danger and that the assailants are being hunted.
04:20 (03:20 GMT) Shots ring out in the Rue du Corbillon, a few minutes' walk from the town hall of this rundown suburb of Paris, as anti-terrorist police raid a third-floor flat
07:03 Shooting continues intermittently - at least one person killed inside the flat and two police officers injured
07:20 Multiple explosions and intense gunfire heard
07:40 Local residents urged to stay indoors by the authorities
07:56 Police sources report two deaths in the flat, including that of a woman who set off a bomb belt, and three more officers injured
09:17 Prosecutors announce the arrest of three men inside the flat, and a man and a woman nearby
11:26 Police announce end of operation
19:10 Paris prosecutor confirms arrests and says evidence suggests a new terrorist plot was foiled.
Five members of the Raid police anti-terrorism unit were lightly injured in the Saint-Denis operation while a Raid "assault dog", a seven-year-old Belgian Shepherd called Diesel, was killed.
More than 400 people were wounded in Friday's attacks. Three of them are in a life-threatening condition.
IS said it had carried out the attacks in response to France's air campaign against its leadership in Syria, and pledged further bloodshed.
French President Francois Hollande said on Wednesday that IS threatened the whole world and he would be seeking a "large coalition" to work together to defeat the militant group.
What is Islamic State?
IS is a notoriously violent Islamist group which controls large parts of Syria and Iraq. It has declared its territory a caliphate - a state governed in accordance with Islamic law - under its leader Abu Bakr al-Baghdadi.
What does it want?
IS demands allegiance from all Muslims, rejects national borders and seeks to expand its territory. It follows its own extreme version of Sunni Islam and regards non-believers as deserving of death.
How strong is IS?
IS projects a powerful image, partly through propaganda and sheer brutality, and is the world's richest insurgent group. It has about 30,000 fighters but is facing daily bombing by a US-led multi-national coalition, which has vowed to destroy it.