The fire broke out in Jabaliya refugee camp, Gaza’s Interior Ministry said. A preliminary investigation found a large amount of gasoline inside the building, which contributed to the escalation of the fire, it added.
Everyone in the building was killed, ministry spokesman Iyad Al-Bazm said.
The dead included entire families, local media reports said, listing a doctor, a local government official and a pharmacist, and their wives and children among the victims.
Hussein AlSheikh, the Palestine Liberation Organization’s (PLO) executive committee secretary general, called on Israel to open the Erez crossing to allow the wounded to be transported to hospitals outside Gaza.
Israel’s Defense Minister Benny Gantz said it would be right for Israel to do in order to save human lives, but it appears that there were no wounded survivors to transport.
Israel controls the Erez crossing, one of the few checkpoints allowing movement between Israel and Gaza.
Police forces, civil defense and forensic teams are still investigating the incident, Gaza’s Interior Ministry said.
Many families living in Gaza stockpile gasoline and diesel to power generators, since the territory has electricity for only eight hours a day as it only has one power station.
Hamas, the militant movement which runs Gaza, expressed sorrow over the deaths and called on the Palestinian people to participate in the victims’ funerals on Friday.
Palestinian Authority President Mahmoud Abbas declared one day of mourning for the victims.