A large fire that ripped through a home north of Gaza City killed at least 21 people including seven children on Thursday, official and medical sources said.
Hamas members, who control the Israeli-blockaded Palestinian enclave, said that firefighters had managed to contain the blaze in Jabalia.
Gaza's civil defense unit confirmed in a statement that 21 people had been killed.
The head of the Indonesian Hospital in Jabalia, Saleh abu Laila, told AFP that the facility had received the bodies of at least seven children killed.
While the cause of the fire remained unknown, a spokesman for the civil defence unit told AFP that supplies of fuel were being stored in the house.
The Palestinian Authority, based in Israeli-occupied West Bank -- a separate Palestinian territory -- offered to send help.
President Mahmud Abbas “gave instructions to send all forms of medical and other urgently needed assistance,” senior PA official Hussein Al Sheikh said on Twitter.
He also urged Israel to open the Erez crossing that connects Gaza with southern Israel and is normally closed at night.
“We called on the Israeli side to open the Erez crossing to transport dangerous cases in order to treat them outside the Gaza Strip if necessary,” Al Sheikh said.
A spokesman for COGAT, the Israeli defense ministry unit that manages the Erez crossing, told AFP that Israel “will provide help... as needed” through the transit point.
A large crowd of onlookers gathered on the street outside the multi-story home as the blaze raged, sending plumes of smoke billowing out the top of the building.
Jabalia is a refugee camp, but like many such Palestinians camps, now includes large buildings and in many respects resembles a city.
Gaza, densely populated with 2.3 million people, has been under Israeli blockade since 2007, a measure Israel says is necessary to contain threats from armed groups in the strip.
With electricity supply sparse in the impoverished territory, domestic blazes are common, as Gazans seek alternative sources for cooking and light, including kerosene lamps.
This year Gaza received an average of 12 hours of mains electricity daily, up from just seven hours five years ago, according to United Nations data.
New dangers arise in the winter when many people burn coal for heat.
Hamas said an investigation was underway to determine the cause.