Three jihadists were killed, including a woman who blew herself up, in a shootout on Wednesday on the northern edge of the city as the French police launched a massive manhunt for Abdelhamid Abaaoud, the mastermind behind the Paris attacks, reports said.
As many as seven deafening blasts shook the Paris suburb and heavy gunfire broke out at about 4.30 am when the police surrounded an apartment where Abaaoud along with other suspects in the November 13 Paris attacks that left at least 129 dead are believed to be holed up.
Islamic State claimed responsibility for the series of coordinated terror attacks that rocked the French capital on Friday night.
Residents of Saint-Denis were asked to clear the vicinity of the operation that started at 4.30 am on Wednesday, Aljazeera reported. The shots ceased after 15 minutes and then resumed at 5 am.
According to reports, two suspects have been arrested while the French military has been deployed at the site amidst heavy gun firing.
Christian, a resident of Saint Denis' rue de la République, told local French channel BFMTV that there was noise of gunfire and police fired shots into an apartment. Later blasts smashed the windows in the flat and a mattress was flung out of the window, The Telegraph reported.
A passer-by was killed during gunfire, reported Xinhua, citing BFMTV.
Another suspect, Salah Abdeslam, was also said to be a target in the raid.
Heavily armed special police units and ambulances gathered at the scene as a helicopter hovered over the area.
Al Jazeera described Saint-Denis a relatively poor area, housing many immigrants. It is near the area of the national stadium Stade de France, where suicide bombers had struck on Friday.
Three suspects, including a woman who blew herself up, have died while another two have been arrested.