“The generators of the complex stopped and the power was cut off,” the ministry said, raising fears over the fate of six other patients in intensive care and three children in a nursery at the Nasser hospital in the southern city of Khan Yunis.
“We hold the Israeli occupation responsible for the lives of patients and staff considering that the complex is now under its full control,” it said in a statement.
The military when contacted by AFP said it was checking the report of fatalities at the hospital.
A witness, who declined to be named out of fear for their safety, said army snipers shot “at anyone who moved inside the hospital” and that “military vehicles surrounding” it also opened fire.
On Thursday the ministry said hundreds of people, including patients and medical staff, had still been inside the hospital complex.
The Israeli army said Thursday it had launched a “precise” operation in the hospital after receiving “credible intelligence” to suggest hostages had been held inside, and that the bodies of hostages may be in the facility.
But later Thursday the army said it had “not yet found any evidence of this”, although forces had found “weapons, grenades and mortar bombs” at the hospital complex.
For weeks, thousands of people displaced by the war have taken refuge at the complex.
Medical charity Doctors Without Borders (MSF) said on Thursday that shelling of the hospital had forced its staff to flee, leaving patients behind.