French riot police (CRS) secure the area as shots are exchanged in Saint-Denis, France, near Paris, November 18, 2015 during an operation to catch fugitives from Friday night's deadly attacks in the French capital.[Photo/Agencies]

SAINT DENIS, France - Gunfire and explosions shook the Paris suburb of St. Denis early on Wednesday when French police raided an apartment where a Belgian Islamist militant suspected of masterminding last week's attacks in the French capital was possibly holed up.

A woman died after detonating a bomb at the scene, the French prosecutors' office said, adding that three people in the apartment had been arrested and two others were seized nearby.

A judicial source said a second person had died in the pre-dawn raid and two more suspects arrested in the operation to hunt down those responsible for coordinated suicide bombings and shootings that killed 129 people in Paris.

Seven hours after the operation started, police announced it was over, but there was still no word on whether militant Abdelhamid Abaaoud, who was initially thought to have orchestrated Friday's attacks from Syria, had been caught.

Heavily armed police and soldiers filled the streets of St. Denis, schools and shops were shuttered and residents in the heart of the district were ordered to stay at home.

Local residents spoke of their fear and panic as the shooting started just before 4.30 a.m. (0330 GMT).

"We could see bullets flying and laser beams out of the window. There were explosions. You could feel the whole building shake," said Sabrine, a downstairs neighbour from the apartment where at least one gunman was still believed to be holed up.

She told Europe 1 radio that she heard the people in the flat above talking to each other, running around and reloading their guns.

"I tried to hide my son beneath me but each time there was shooting he was clawing at my skin," she said, adding that police eventually managed to get them to safety.

Three police officers and a passerby were injured in the assault, which was close to the Stade de France stadium which was one of the targets of the Nov. 13 attacks.

FLEEING RAQQA

Police investigating the worst atrocity in France since World War Two soon linked the carnage to a militant cell in Belgium which was in contact with Islamic State in Syria.

The group claimed responsibility for killings, saying they were in retaliation for French air raids in Syria and Iraq over the past year. France has called for a global coalition to defeat the radicals and has launched three large air strikes on Raqqa -- the de-facto Islamic State capital in northern Syria.

Russia has also targeted the city in retribution for the downing of a Russian airliner last month that killed 224 people.

The Syrian Observatory for Human Rights monitoring group said on Wednesday the bombardments have killed at least 33 Islamic State militants over the past three days.

Citing activists, the Observatory said Islamic State members and dozens of families of senior members had started fleeing Raqqa to relocate to Mosul in neighbouring Iraq.