A police official said one person was still holed up in a besieged apartment in the North of Paris where two people have been killed and five have been arrested.
A number of French police are reported to have been injured in the siege.
Investigators have identified 27-year-old Abdelhamid Abaaoud, a Belgian of Moroccan descent, as the chief architect of Friday’s attacks in Paris.
A US official said Abaaoud was a key figure in an Islamic State external operations cell that US intelligence agencies have been tracking for months.
Residents said an explosion shook the neighbourhood at about 4am local time.
“Then there was second big explosion. Then two more explosions. There was an hour of gunfire,” said Baptiste Marie, a 26-year-old independent journalist who lives in the neighbourhood.
Another witness, Amine Guizani, said he heard the sound of grenades and automatic gunfire.
“They were shooting for an hour. Non-stop. There were grenades. It was going, stopping. Kalashnikovs. Starting again,” Mr Guizani said.
Saint-Denis mayor Didier Paillard said public transport was suspended and schools in the centre of town would not open on Wednesday.
Seven attackers died in Friday’s gun-and-bomb rampage through Paris. The Islamic State group has claimed responsibility for the carnage.
Bon c'est sur c'est une intervention de la police... rue barrée, officiers etc.. #SaintDenis pic.twitter.com/JSARgbaM9w
— Lunaticwolf 🇭🇹 (@Chelmih) November 18, 2015
Police had said before the raids that they were hunting for two fugitives suspected of taking part as well as any accomplices. That would bring the number of attackers to at least nine.
French authorities had previously said that at least eight people were directly involved in the bloodshed: seven who died in the attacks and one who got away and slipped across the border to Belgium.
Euh ouais ? #fusillade #SaintDenis pic.twitter.com/cdAzDDtu2R
— Morgane Duval (@Siamelfe) November 18, 2015
President Francois Hollande has held an emergency meeting at the Elysee Palace to monitor the raid.
Prime minister Manuel Valls, interior minister Bernard Cazeneuve, defence minister Jean-Yves Le Drian, foreign minister Laurent Fabius and justice minister Christiane Taubira were in the meeting.