Thirty-seven people have been injured, four of them seriously, after a large explosion in central Paris, authorities said.
The blast took place on Wednesday in a building that housed a design school and the Catholic education system headquarters in Rue Saint-Jacques, in the fifth arrondissement of the French capital, BBC reported.
Emergency workers are searching through the wreckage of the building, with atleast two reported to be missing.
According to witnesses, there was a strong smell of gas before the blast, BBC reported.
Paris prosecutor Laure Beccuau said after arriving at the scene that initial checks of camera footage suggested the explosion occurred within the building, which was next to the Val de Grace church.
However, the authorities have said the cause of the blast has not yet been determined, BBC reported.
The building was initially engulfed by fire, but the blaze was later brought under control, said Paris police chief Laurent Nunez.
The area has been cordoned off and Interior Minister Gerald Darmanin has been to the scene.
He said sniffer dogs had identified where further victims might be found under the rubble.
The area where the explosion took place runs south from the Latin Quarter in Paris's Left Bank area that is popular with tourists and known for its student population.
A student at Ecole des Mines on Boulevard Saint-Michel told Le Parisien: "I was in front of the Val de Grace, I heard a huge boom and I saw a ball of fire 20 or 30m high. And the building collapsed with a huge noise. I smelled gas, but took several minutes to come to my senses."
Another witness, Antoine Brouchot, told the BBC he was at home when he heard a "big explosion".
"I stuck my head out of the window and looked towards Cochin (hospital), then I saw a big cloud of smoke and as I got closer, there was a building that had collapsed and for the moment, there is a fire."
(With inputs from IANS)