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 2 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 authorized 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.

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 organization in Brussels.

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The group — which says it only runs programs 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 organization 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 organization. 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.

“We are very concerned with the way things are going at this point because it looks like it’s going to get worse – very soon,” Quemin said. The sealing of Gaza, he said, will create “humanitarian needs very quickly.”

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Governments have also been weighing how to respond.

As the fighting intensified, the European Union on late Monday reversed an earlier announcement by an EU commissioner that the bloc was “immediately” suspending aid for Palestinian authorities. Instead, the 27-nation group said it would urgently review the assistance it provides in the wake of Hamas’ attacks on Israel. Two European countries — Germany and Austria — said they were suspending development aid for Palestinian areas.

Meanwhile, some organizations are stepping up aid efforts in Israel, which has seen displacement because of the violence.

Naomi Adler, CEO of Hadassah, The Women’s Zionist Organization of America, said a trauma center in Jerusalem that’s owned by the organization is treating wounded Israeli soldiers and civilians. About 90% of the patients in the center right now are soldiers, who are typically the first to be brought in for traumatic injuries, Adler said. But the center also accepts anyone who’s wounded or injured in the country.

The American Jewish Joint Distribution Committee, a Jewish humanitarian organization, said on Sunday that it was activating its emergency response team in Israel, where it runs programs to support people with disabilities, the elderly and children and families who’ve been impacted by the war and prior conflicts. The organization said it was working with its partners, including in the Israeli government, to address what it called an unprecedented emergency.

JDC’s CEO Ariel Zwang said among other things the nonprofit is helping teachers, social workers and other caregivers provide support to those who’ve suffered trauma and tragedies from the events of the past few days. She said it will help nursey teachers, for example, explain to children why some of their classmates are suddenly missing.

“If you’re a teacher now, if you know the children are traumatized, you need special skills and special training in order to manage what you’re experiencing and provide for the emotional needs, which are extraordinary at this time, of your youngest charges,” Zwang said.

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One organization that helps Palestinian children is shifting its focus, too. Steve Sosebee, the president of Palestine Children’s Relief Fund, a U.S.-based charity that helps children in need travel to the U.S. for medical treatment, said given the war, the fund is now looking away from long-term programs and toward more urgent needs for food, medication, clothing and other types of basic humanitarian aid. But like others, he noted the blockade and security risks to its Gaza staff makes it more challenging to do that.

“There are no areas of security, there are no safe havens,” Sosebee said. “And therefore, it’s very difficult for us to be out in the field providing humanitarian aid when there are no safe places from the constant bombing and attacks that are taking place over the last 72 hours.”

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