By Yiming Woo and Sarah Meyssonnier
VAULX-EN-VELIN, France (Reuters) -Ten people including five children aged three to 15 were killed in a fire on Friday that engulfed a residential building in an impoverished town near the southeastern French city of Lyon.
Another four people were seriously injured in the blaze in Vaulx-en-Velin, which started around 3 a.m. (0200 GMT) on the ground floor before spreading up the seven-storey building, rescue authorities said.
Footage on social media showed a huge, dark cloud billowing above the building at the time of the fire before it was extinguished after daybreak.
Witnesses in nearby buildings said they had been woken up by screams and felt helpless as they stood at the foot of the building on fire, the smoke too thick for them to get in and try to rescue residents before firefighters arrived.
"At around 3.30 a.m., I heard shouting so I ran out of my home...I saw the building, number 12, on my left burning on the ground floor...and people trying to get out," said Furkan Bag, a neighbour and restaurant owner.
He saw a woman jumping out of a window to escape the flames and smoke, and falling to her death.
"The fire was growing bigger and bigger ... it was at the entrance of the building, they (rescue) could not get in."
The Lyon prosecutor's office opened an investigation to determine how the fire broke out, and said it could not rule out any hypothesis including arson.
Angry neighbours told reporters they felt abandoned by public authorities, amid local media reports that the building hit by the fire had been in poor condition and the ground floor occupied by drug dealers.
A third of Vaulx-en-Velin's population lives under the poverty threshold, in what is one of France's many highrise areas hastily developed in the second half of the 20th century to ease a housing shortage and accommodate waves of immigrants.
"Everyone knows where the drug dealing spots are. Why do they wait for there to be deaths before acting?" Nordine Gasmi, an opposition party councillor in the Vaulx-en-Velin town hall, told reporters.
"This was bound to happen," he said. "People here are living through hell."
Socialist Mayor Helene Geoffroy said now was the time for mourning, and talk about the roots of the problem would come later. Some buildings in the area had been refurbished and more works were planned for others, she said.
Interior Minister Gerald Darmanin, who visited the site of the fire on Friday, confirmed there was drug dealing - and squatting by drug dealers - in several spots along that street, including within the building hit by the blaze. Police had arrested drug dealers in that building overnight, he said.
"There had been reports of drug dealing but it's too early to draw conclusions" on what caused the fire, Darmanin said.