NEW YORK (AP) — Humanitarian groups are scrambling to assist civilians caught in the war between Israel and Hamas and determine what aid operations are still safe to continue — efforts that are being complicated by an intensified blockade of Gaza and ongoing fighting.

Two days after Hamas militants went on a rampage that took the world by surprise, Israel increased airstrikes on Gaza and blocked off food, fuel and other supplies from going into the territory, a move that raised concerns at the United Nations and among aid groups operating in the area home to 2.3 million people. Hamas, in turn, pledged to kill Israelis it abducted if the country’s military bombs civilian targets in Gaza without warning.

Hundreds of people have been killed and thousands wounded on both sides, and aid groups operating in the region say there are needs both in Gaza and Israel.

More than two tons of medical supplies from the Egyptian Red Crescent have been sent to Gaza and efforts are underway to organize food and other deliveries, according to an Egyptian military official, who spoke on condition of anonymity because he was not authorised to talk to the press. But the United Nations and other aid groups are pleading for more access to help Palestinians who find themselves in the middle of intense fighting.

The UN and other aid agencies were talking with Egypt to send humanitarian aid to the besieged Gaza through a crossing point between the strip and Egypt’s Sinai Peninsula, an Egyptian official and aid worker said Tuesday. Meanwhile, the World Health Organization said Tuesday medical supplies it has in seven hospitals in Gaza had already been used up and it was reprogramming funds to purchase more from local markets.

Doctors Without Borders, which is still operating in Gaza, has to rely on supplies it already has inside the territory because it can’t bring any more in, said Emmanuel Massart, a deputy desk coordinator with the organisation in Brussels.

The group — which says it only runs programmes in Palestinian areas since Israel has strong emergency and health services — reported Monday that it provided treatments to more than 50 people following airstrikes at the Jabalia refugee camp located north of Gaza City. In addition to helping patients in Gaza, it said it was donating medical supplies to other clinics and hospitals, which have become overcrowded with patients and are experiencing shortages of drugs and fuel that can be used for generators.

If Doctors Without Borders is not able to resupply fairly quickly, Massart said, it will run out of supplies it can use to operate on patients who might be wounded. He also said since the facilities the organisation uses are running on generators due to the low supply of electricity, cutting off fuel will present a “huge problem.”

“If there is no fuel anymore, there is no medical facilities anymore because we cannot run our medical facility without the energy,” Massart said.

The war has also been deeply disruptive to work Mercy Corps has been doing to provide people in Gaza with necessities like food and water, said Arnaud Quemin, the Middle East regional director for the organisation. Right now, he said the team on the ground is trying to find a scenario that would enable them to get back to work. The blockade of food and other supplies into Gaza is a major worry.