GAZA CITY/GENEVA/CAIRO (Reuters) -The hunger crisis in Gaza is at a tipping point, with critically low supplies of fortified milk and special nutritious pastes exacerbating food shortages and pushing greater numbers of children into starvation, according to aid agencies, malnutrition experts and the United Nations.

A whistleblower claims World Food Programme and U.N. agencies rejected Israeli security assistance, blocking aid distribution to Gaza despite available supplies as U.N. dismisses accusations.

The United Nations (UN)-backed group that monitors food insecurity and malnutrition is expected to formally declare a famine in the Gaza Strip. For several months, the Palestinian enclave has been in the grips of a severe hunger crisis as a result of Israeli policy of restricting the flow of humanitarian assistance.

An eyewitness told CBS News that American subcontractors at Gaza Humanitarian Foundation sites shot at Palestinians, a claim GHF denies.

As aid fails to reach civilians in Gaza, Israel slams misleading figures. The U.S.-backed Gaza Humanitarian Foundation, using armed security, continues to feed millions despite a U.N. boycott.

Thousands of Palestinians have fled their homes in Gaza City, as the Israeli military continues its assault on the enclave ahead of a planned occupation.

Democrat U.S. Senators Call for Investigation, Sanctions for Israeli Settlers’ Violence and Obstruction of Aid in Gaza