Video shows fire ripping through a building in Paris, after a gas leak in the city's Val de Grâce district
At least 24 people have been injured, including four who are in a critical condition, in an "extremely violent" explosion at a school in Paris.
Emergency services searching the wreckage on Wednesday evening said people were still missing, and they are investigating whether a gas leak triggered the incident.
Police evacuated residents and workers from Rue Saint-Jacques in the Val de Grâce district, on Wednesday after the incident at a private school, the Paris American Academy, according to a chief officer.
Some 270 firefighters descended on the building to tackle the blaze and 70 emergency vehicles were sent the city's 5th arrondissement.
Fire crews are searching for two people who may still be trapped inside the building which is still ablaze, Paris police said.
Paris police said they are investigating suspicions that a gas leak caused the explosion.
They said the facade of the 5th arrondissement building that housed the school collapsed, and emergency services were searching for two people believed to be still inside.
The Paris prosecutor said an investigation was opened into aggravated involuntary injury and the probe would examine whether the explosion stemmed from a suspected violation of safety rules.
Fire sparked and smoke filled the air over the Pantheon monument, near the historic Val de Grace military hospital on Wednesday evening.
Authorities said the injuries were mainly caused by people being blown off their feet by the blast.“The explosion was extremely violent,” Florence Berthout, mayor of the arrondissement said, as she described pieces of glass still falling from buildings.
Laurent Nuñez, the Paris police chief, said firefighters managed to stop the flames spreading to two buildings which had been “seriously destabilised” by the explosion and evacuated.
The explosion blew out several windows in the area, witnesses and the police chief said.
Achille, a student, said he was in a building about 100 metres from the explosion.
“I was sitting on the windowsill, and we moved two meters away from the window, carried by a small blast (from the explosion) and huge fear," he told BFM television.
“We came down (from the building) and saw the flames," he said. “The police gave us great support and we evacuated quickly.”
The Paris police chief said the building where the explosion occurred was a private school, the Paris American Academy, which was founded in 1965.
The school offers lessons in fashion design, interior design, fine arts and creative writing to what appears to be students of college or university age.
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