Two people have reportedly been killed and seven arrested after French police swooped on an apartment in Saint-Denis, a northern suburb in Paris, early Wednesday morning.
One of the two people killed was a female who detonated a suicide belt.
Five officers sustained minor injuries during the operation, which started at around 4.30 a.m. and ended just before midday local time. A police dog, a seven-year-old Belgian Shepherd Dog called Diesel, was "killed by terrorists," the National Police said.
[INFO] #SaintDenis Opération #RAID en cours À cette heure, 5 policiers du #RAID sont légèrement blessés.— Police Nationale (@PNationale) November 18, 2015
Police encountered fierce resistance during the raid, which went on for more than seven hours. Gunfire and explosions were heard and dozens of police officers surrounded the address. No hostages were thought to be involved.
27-year-old Belgian Abdelhamid Abaaoud, the suspected mastermind of Friday's attacks, is believed to be the focus on the raid. He was previously thought to have been in Syria.
Deputy Mayor Stephane Peu urged local residents to stay indoors during the raid, saying "it is not a new attack but a police intervention."
Authorities evacuated some 20 residents from the building earlier in the night. A city official told the Associated Press that they were brought to the city hall, around 200 meters away, for protection.
The raid took place around a mile (1.6 km) from the Stade de France stadium, where three suicide bombers blew themselves up during an international soccer match between England and France on Friday as part of the coordinated attacks that left 129 dead.
Baptiste Marie, a 26-year-old independent journalist who lives near the scene of the standoff, told the Associated Press: "It started with an explosion. Then there was second big explosion. Then two more explosions. There was an hour of gunfire."
"There were grenades," local resident Amine Guizani said. "It was going, stopping. Kalashnikovs. Starting again."
A helicopter flew overhead as police vans and fire trucks rushed to the scene.
Photos from the scene appeared to show a half naked person led away by a group of police officers in helmets.
As the incident came an end, police tried to knock down the door of a church nearby.
Police in Saint Denis trying to knock down the door of a church close to the flat that was raided this morning pic.twitter.com/BUB4DhBfha— Greg Dawson (@Gregstweet) November 18, 2015
Interior Minister Bernard Cazeneuve spoke shortly after the end of the raid was confirmed, thanking police for their "extremely courageous" efforts. Paris prosecutor Francois Molins said authorities were still working to identify who was inside the apartment.
The Associated Press contributed reporting.