He gave the names and ages of three of the children – Mahmud Abedin, 12, Nabeel al-Astal, 12, and Ashraf al-Najjar, 13 – but no further details.
The deaths raised Thursday’s toll in Gaza to 93, according to Qudra’s figures, with 788 killed in total and more than 5 000 wounded.
Those numbers do not include more than a dozen Palestinian militants killed after infiltrating southern Israel since the conflict began on 8 July.
Among those killed on Thursday were seven who died in air strikes and tank fire in and around Khuzaa near Khan Yunis in southern Gaza.
Five people from the Abu Daqqa family were killed along with two from the Najjar family, Qudra told AFP.
Areas east of Khan Yunis near the Israeli border have come under heavy bombardment in recent days, with emergency services trying to coordinate with the Red Cross to gain access to evacuate civilians.
“We have been receiving dozens of appeals from residents of Khuzaa, Abasan and Bani Suheila in Khan Yunis asking us to evacuate them, and saying there were a lot of people killed and injured underneath the rubble of their houses,” Qudra said.
So far, 32 Israeli soldiers have been killed since the beginning of the conflict, along with two Israeli civilians and one Thai farm worker.
The army’s losses are its heaviest since a 2006 war with Lebanese militant group Hezbollah.