Described as a “scene of incredible violence”, the blaze in the capital's 16th arrondissement also left one person seriously injured and another 30 — including six firefighters — with minor injuries.

The fire started at about 1:00 am (0000 GMT) and was finally brought under control more than five hours later. The latest reports say the blaze is believed to have been started on purpose. A criminal investigation has been opened after a woman was arrested at the scene.

Pictures from the fire brigade showed flames leaping out of top floor windows and firemen climbing flimsy ladders to rescue terrified residents from thick black smoke.

A local resident, Jose Emilien, was standing at a police cordon on Tuesday morning anxiously seeking news of his cousin and nephew who lived on the sixth floor of the building.

“I called both of them,” he told AFP. “They're not picking up and I don't have any news.” 

Fire service spokesman Captain Clement Cognon told AFP at the scene “the toll could still increase” because firefighters were yet to search the upper floors of the eight-storey block, “where the fire was the most violent”.

Some of those affected scrambled on to nearby roofs to escape the smoke and flames, and needed to be rescued by fire crews.

“At first we thought it was a fight, we could hear a woman screaming really loud,” a local resident who gave his name as Nicolas told AFP.

“She was screaming, screaming and we went outside and the building was already on fire. The firemen had just arrived but what was amazing was that they were completely impotent.

“They had the trucks, the big ladders, but they couldn't do anything,” he explained.

The residential neighbourhood lies on the edge of the vast Bois de Bologne park and close to the stadium of top football club Paris Saint-Germain, the Parc des Princes, in the southwest of the city.

Captain Cognon added: “We had to carry out many rescues, notably for around a dozen people who had taken refuge on the roofs. In total about 50 people were evacuated by firefighters, including through the installation of ladders.”

Fire crews evacuated the 1970s block on rue Erlanger and fought the flames through the night. 

Two adjacent buildings were also evacuated as a precaution and local officials were on site to help find housing for residents who could not return to their homes.

Around 200 firefighters were involved in the effort overall, battling the blaze and treating the injured.

Several streets were cordoned off by police and fire crews, and an AFP journalist said a strong smell of smoke hung in the air. 

“Paris is in mourning this morning,” mayor Anne Hidalgo tweeted. 

She along with other politicians including Interior Minister Christophe Castaner were expected to visit the scene amid fears the death toll could rise further.

The blaze follows a fire caused by a powerful gas explosion last month that killed four people in the city's central 9th arrondissement.

In late December, two women and two girls died from asphyxiation in a fire that broke out in a public housing block in a suburb northeast of Paris.