The population of Gaza has fallen 6% since the war with Israel began nearly 15 months ago as about 100,000 Palestinians left the enclave while more than 55,000 are presumed dead, according to the Palestinian Central Bureau of Statistics (PCBS).
Around 45,500 Palestinians have been killed since the war began but another 11,000 are missing, the bureau said, citing numbers from the Palestinian Health Ministry.
As such, the population of Gaza has declined by about 160,000 during the course of the war to 2.1 million, with more than a million or 47% of the total children under the age of 18, the PCBS said.
Israel's foreign ministry said the PCBS data was "fabricated, inflated, and manipulated in order to vilify Israel".
The PCBS said some 22% of Gaza's population currently faces catastrophic levels of acute food insecurity, according to the criteria of the Integrated Food Security Phase Classification, a global monitor.
Included in that 22% are some 3,500 children at risk of death due to malnutrition and lack of food, the bureau said.
Reporting by Maytaal Angel and Ali Sawafta