- After Hamas' attacks on Israel over the weekend, Gaza is under siege.
- Israel has cut off food, water, fuel, and electricity to the Palestinian enclave.
NGOs operating in Gaza are fast running out of supplies.
"Absolutely no humanitarian aid is getting into Gaza," Ivan Karakashian, the head of advocacy in Jerusalem for the NGO Norwegian Refugee Council, told Insider.
Karakashian said his group is currently "distributing what we have in stock and available locally within Gaza, but the blockade restrictions mean that aid agencies can't bring in more aid from outside."
"Water, fuel, and other essential supplies are running dangerously low," he added.
Israel cut off food, water, fuel, and electricity to Gaza after the militant Palestinian group Hamas launched deadly strikes on Israel and took civilians hostage over the weekend.
Israel said more than 100 people were taken hostage and 1,300 people killed in the weekend's attacks.
In response, Israel declared a state of war on Sunday and announced a "complete siege" of Gaza on Monday.
Israel's Air Force has pummeled Gaza, saying it has bombed the strip 6,000 times and will continue to do so, "forcefully and relentlessly."
Israel's attacks have killed more than 1,500 people, the Palestinian health ministry said, with the UN saying 423,000 people have been displaced.
Late on Thursday, Israel said that civilians living in northern Gaza needed to evacuate the area within 24 hours, suggesting that things were about to get much worse.
The UN said evacuating 1.1 million people would be impossible "without devastating humanitarian consequences."
More than two million people are trapped in the enclave, one of the world's most densely populated places, with supplies dwindling.
Alun McDonald, a spokesperson for Islamic Relief Worldwide, told Insider there is a "huge challenge with procuring more supplies."
He said the group is currently "distributing what we have in stock and available locally within Gaza, but the blockade restrictions mean that aid agencies can't bring in more aid from outside."
Karakashian said his NGO's staff in Gaza are reporting empty shops.
Many human rights advocates say Israel's siege of Gaza, which it said it will enforce until the hostages are freed, violates international law.
Israel's heavy strikes are also limiting what aid workers can do, the groups say.
Karakashian said his group has 52 employees in Gaza, some of whom have been displaced.
He said there needs to be humanitarian corridors and a pause that allows humanitarian personnel and supplies to enter. Without that, he said, "we will not be able to provide life-saving assistance."
McDonald said that "the security situation makes it extremely dangerous to deliver aid – even ambulances and medical teams have been hit by bombs – and some areas are inaccessible due to the bombing."
He said his group has mainly focused on delivering medical supplies and drugs for hospitals and health facilities, describing those as "particularly overwhelmed right now."
But those deliveries have been "very limited given the scale of the needs," he said.
Doctors Without Borders told Insider that many of their patients in Gaza have been children, and that they are limited in their treatment because it is so hard for patients and doctors to move around.
Almost half of Gaza's population is under 18, meaning around one million children are at risk.