Up to 10 people were thought to be under the rubble after an explosion that caused two residential buildings to collapse in the southern French city of Marseille on Sunday, Interior Minister Gerald Darmanin said.
The cause of the explosion was not yet known.
The collapse caused a fire that complicated rescue efforts and that Darmanin said could take hours to put out. He said authorities estimated there were between four and 10 people under the rubble.
Five people were taken to hospital with serious but not life threatening injuries and a sixth person was being treated for shock, he added.
A third building has partially collapsed and people have been evacuated from some 30 buildings in the area.
The buildings that collapsed on the Rue de Tivoli were not known to have any structural problems, Darmanin said.
"Thoughts are with Marseille," President Emmanuel Macron said in a Twitter message.
Israeli Prime Minister Benjamin Netanyahu said on Sunday Israel would determine which foreign forces it would allow as part of a planned international force in Gaza to help secure an end to its war under US President Donald Trump's plan.
Two suspects in the brazen daylight heist of some of France's crown jewels from the Louvre were arrested in Paris on Saturday evening and are being questioned, Le Parisien newspaper reported on Sunday, citing sources close to the investigation.
Ukraine's President Volodymyr Zelenskyy called for new strong sanctions against Russia and its allies after Russian drones killed three and injured 31, including six children, in an overnight air attack on Kyiv.
The outlawed Kurdistan Workers Party (PKK) said on Sunday it was withdrawing from Turkey as part of a disarmament process it is coordinating with the government, and pressed Ankara for concrete measures to move the process along.