"We are horrified to see the destruction in #JabaliaRefugeeCamp in #Gaza #OccupiedPalestinianTerritory, killing and injuring even more families," the UK-based humanitarian organization’s country director Jason Lee said on X.
"Civilians must be protected," he added.
A series of Israeli airstrikes on the refugee camp led to hundreds of casualties, according to the Interior Ministry in the besieged enclave.
Most of the victims were women and children, it said, adding that Israeli warplanes destroyed the entire residential square known as Block 6.
The Israeli army has expanded its air and ground attacks on the Gaza Strip, which has been under relentless airstrikes since the Palestinian group Hamas launched a surprise cross-border offensive against Israel on Oct. 7.
The death toll from ongoing Israeli attacks in the Gaza Strip has climbed to 8,525, the Health Ministry in the blockaded enclave said Tuesday.
“The victims include 3,542 children and 2,187 women, while 21,543 other people were injured,” ministry spokesman Ashraf al-Qudra told a press conference in Gaza City.
Israeli Prime Minister Benjamin Netanyahu has rejected growing calls for a cease-fire, saying it would be a "surrender" to Hamas.
An Israeli blockade of the Gaza Strip has also cut off fuel, electricity and water.
Reduced aid deliveries are unable to satisfy the needs of its more than 2 million residents.