Palestinians across the besieged Gaza Strip have described their terror and confusion, as thousands fled a wave of Israeli airstrikes after Hamas’s unprecedented cross-border incursion. “When we began asking about the situation inside the hospitals we work with, one person described it as a slaughterhouse,” said Mahmoud Shalabi of Medical Aid for Palestinians, who is overseeing support to hospitals across the Gaza Strip. “There were bodies laying on the ground, there wasn’t enough space in the emergency department and they were struggling to deal with the influx they were seeing. “The situation is really dire at the moment, we have been facing one of the toughest escalations as Palestinians in Gaza.” Israel pummelled Gaza, a slim strip of land home to about 2 million people, striking it from the sea and air overnight and into the following day. “For your safety, immediately evacuate the areas where you live,” Avichay Adraee, a military spokesperson, instructed civilians in Gaza, writing on X, the platform formerly known as Twitter. Many across Gaza feared there was nowhere to hide, in a 140 square mile area that has long been considered one of the most densely populated areas on Earth. Shalabi said aid groups working inside Gaza estimated that at least 20,000 people were displaced on the first night of Israeli airstrikes. Thousands fled into Gaza City, already the most tightly populated area of the Strip, which witnessed airstrikes on tower blocks and other infrastructure. Israeli forces claim they had selected targets linked to Hamas, while Palestinians based in Gaza accuse the Israeli military of striking civilian and residential infrastructure with tenuous connections to the militant group, which has ruled Gaza since an election in 2006. “It’s been very worrying as you can imagine; there was a bombardment every 15 to 30 minutes throughout the night,” said Mohammed Ghalayini, an air quality scientist living in Manchester who had returned to Gaza for a rare visit to see family. “Many people have been leaving their homes for places that are apparently safer – a friend in eastern Gaza has 80 relatives and neighbours staying with him in their block. My uncle in Khan Yonis has friends staying with him seeking refuge from their own homes which are on the eastern border [of Gaza].” The airstrikes, drone strikes and artillery fire from ships on the Mediterranean came after Israel’s prime minister, Benjamin Netanyahu, declared that his country was “at war”. He vowed to enact an “immense price from the enemy”, after Hamas militants staged an unprecedented incursion into southern Israeli territory, capturing at least 100 Israelis and leaving at least 250 dead. The Palestinian health ministry said at least 300 were killed overnight from Israeli airstrikes, including children, with almost 2,000 wounded. Ghalayini said Palestinians were awed by the unprecedented nature of Hamas’s incursion into Israeli territory. But, he added, this was not without widespread fear. “People are also very fearful of what’s to come. But Palestinians, especially in Gaza, have suffered so much over the past 15 years of blockade and attack after attack from Israel, so they feel they have nothing left to lose,” he said. Netanyahu’s pledge to inflict pain on Gaza and target Hamas militants based in the strip follows more than a decade of repeated confrontations between Palestinian militants based in the strip and the Israeli military that has left thousands of civilians dead, as well as Israel’s 16-year blockade of the Gaza Strip. The blockade prevents Palestinians from leaving except in exceptional circumstances, and curtails and controls the flow of goods into the area, particularly construction materials, medical supplies and even food. After a meeting with the Israeli security cabinet, Netanyahu’s office declared they had shut off gas and electricity supplies to Gaza, and blocked goods passing through a border crossing in the north of the strip. Israel’s energy minister, Israel Katz, ordered a halt to Israeli electricity supplies, slashing Gaza’s electricity supply by 80%. “The internet is very weak and there is no power. Even the backup generators that are now a secondary grid for those who can afford them are rationing,” said Ghalayini. Shalabi described an unprecedented emergency situation for medical personnel across the strip, worsened by the lack of electricity as well as years of Israeli attacks that have left Gaza’s medical infrastructure on its knees. “This morning I spoke to another doctor, a general surgeon, working in the central Gaza area. He told me they are lacking greatly medical supplies, drugs, disposables, everything needed in an emergency situation.” “But most importantly there are not enough doctors to deal with the cases and the influx of injuries. [One] person was just starting his general surgery training, but has been managing the general surgery department for almost two days alone, while other seniors are dealing with more serious cases upstairs.” He said his organisation immediately released its entire stock of medical resources including blood supplies, in an unusual move that exceeds their choices during previous Israeli airstrikes and attacks on Gaza. “We are releasing everything at the moment because the situation is going to get really grim, really dire,” he said.