More than 13,800 children have been killed in Gaza since the start of the war, according to UN Children's Fund (UNICEF) Executive Director Catherine Russell.
"Thousands have been injured and thousands more are on the brink of famine," she said during a news conference in New York.
In a separate statement, the UN Entity for Gender Equality and the Empowerment of Women said that "one child is injured or dies every 10 minutes" in Gaza. And that more than 10,000 women have been killed in Gaza since the war began, and 6,000 of them left 19,000 orphaned children behind.
UNICEF communication specialist Tess Ingram, who recently visited Gaza, said in Geneva on Tuesday that what struck her was the number of wounded children she saw.
"Not just in the hospitals, but on the streets, in their makeshift shelters, going about their now permanently altered lives," she said.
CNN cannot independently verify death numbers due to a lack of media access to Gaza.