Gaza was rocked by a series of huge explosions on Sunday evening and communications with the coastal strip were cut, as violence also escalated on Israel’s northern boundary with Lebanon. The strikes on Gaza came as the Israel Defence Forces (IDF) indicated that Israeli troops were planning to enter Gaza City in force perhaps within the next 48 hours, according to reports in Israeli media. Journalists inside Gaza and watching from the Israeli border described intense Israeli strikes on the coastal strip, and video showed towering explosions in the night sky. Reports from Gaza said the strikes were coming from the air, sea and land, including from the north of the strip where Israeli troops now have a presence. In northern Israel, boundary communities, including the city of Kiryat Shmona, came under mortar and rocket fire from Hezbollah after an Israeli strike in southern Lebanon killed three girls aged eight to 14 and their grandmother. A Hezbollah MP called the attack a “dangerous development” for which Israel would pay a price, as Israelis were ordered to shelter in secure rooms and the main road north was closed to traffic. Residents in the north described at least one direct strike on a building in Kiryat Shmona as Hezbollah fired rockets and mortars across the border. Officials said one Israeli was killed. The Lebanese militant faction said in a statement that its attack came in response to Israel’s “heinous and brutal crime”. Earlier on Sunday, officials from Gaza’s Hamas-controlled health ministry accused Israeli jets of striking al-Maghazi refugee camp in central Gaza, killing at least 47 people and wounding dozens. The escalating violence on two fronts came alongside intensifying US diplomacy to try to bring about a pause in the fighting to ease the acute humanitarian crisis in Gaza and to free hostages, amid fears of a regional escalation of the war between Israel and Hamas. The US secretary of state, Antony Blinken, met the Palestinian president, Mahmoud Abbas, in his last stop before leaving for Cyprus and Turkey, after a meeting with Arab leaders on Saturday. A senior state department official said Blinken told Abbas that the Palestinian Authority should play a central role in the future of Gaza. He passed through Israeli checkpoints to enter the West Bank city of Ramallah on his second visit to the region since Hamas fighters launched attacks on southern Israel on 7 October that killed 1,400 people. A spokesperson for Abbas said after the meeting that the Palestinian president had called for an immediate ceasefire and the delivery of humanitarian aid to Gaza and that the Palestinian Authority would only assume power in Gaza as part of a “comprehensive political solution” to the Israeli-Palestinian conflict. The state department spokesperson Matthew Miller said Blinken reaffirmed the US commitment to the delivery of life-saving humanitarian assistance and resumption of essential services in Gaza and made clear that Palestinians must not be forcibly displaced. As Washington, the international community and Israel have struggled to articulate what would happen on the “day after” – should Israel succeed in topping Hamas – the comments, relayed by a senior state department official on Sunday, were the clearest indication yet of US thinking. Abbas and the Palestinian Authority have had no role in governing Gaza since 2007, when Hamas took control of the coastal strip after the Hamas-backed Change and Reform party won the biggest share of the vote in legislative elections in 2006. Last month in an interview with the Guardian, the Palestinian prime minister, Mohammad Shtayyeh, rejected the Palestinian Authority’s return to govern Gaza without a comprehensive agreement that includes the West Bank in a Palestinian state. In Israel, the prime minister, Benjamin Netanyahu, reiterated the government’s longstanding position that there could be no temporary ceasefire until Hamas released its hostages held in Gaza. “There will be no ceasefire without the return of the hostages. This should be completely removed from the lexicon,” he told crews at the Ramon air force base in southern Israel. Blinken has said humanitarian pauses could be critical in protecting civilians, getting aid in and getting foreign nationals out but he has rejected a full ceasefire. “It is our view now that a ceasefire would simply leave Hamas in place, able to regroup and repeat what it did on October 7,” he told the Jordanian foreign minister, Ayman Safadi. At the Maghazi refugee camp in central Gaza, the scene of the latest strike that killed dozens overnight, journalists saw first responders and residents digging through the rubble, hoping to find survivors. An Associated Press reporter at a nearby hospital saw the bodies of at least five children, including an infant who had been pulled from the rubble. Arafat Abu Mashaia, who lives in the camp, said the Israeli airstrike flattened several multistorey homes where people forced out of other parts of Gaza had been sheltering. “It was a true massacre,” he said early on Sunday while standing amid the wreckage of destroyed homes. “All here are peaceful people. I challenge anyone who says there were resistance [fighters] here.” Conditions in Gaza have continued to deteriorate and evacuations of civilians and heavily wounded Palestinians from Gaza have been suspended since Saturday, according to Egyptian security and medical sources, after an Israeli strike on ambulances near the entrance to Gaza City’s main Dar al-Shifa hospital. Israel later claimed Hamas was using an ambulance to move its fighters. Underscoring the nature of a conflict that has come to be dominated by attempts by Israel and Hamas to promote their own diverging narratives, the IDF accompanied a handpicked group of foreign and Israeli reporters into Gaza for a few hours over the weekend to produce reports under Israeli military restrictions. In the last major conflict in Gaza in 2014, international media outlets were able to operate inside the coastal strip, entering from Israel but, in the current conflict, reporters have been denied access either from Israel or via Egypt, while a number of Palestinian journalists operating inside Gaza have been killed during Israeli attacks. The Committee to Protect Journalists has said more media workers have been killed in the Israel-Hamas war than in any other conflict in the area since it started monitoring in 1992. As of Friday, 36 media workers – 31 Palestinians, four Israelis and one Lebanese – had been killed since Hamas attacked Israel on 7 October, according to the group. The soaring death toll in Gaza has sparked growing international anger, with crowds of tens of thousands of people taking to the streets in cities from Washington to Berlin on Saturday to demand an immediate ceasefire. Israel has repeatedly rejected the idea of halting its offensive, even for brief humanitarian pauses proposed by Blinken during his tour of the region. Instead, it said Hamas was “encountering the full force” of its troops. “Anyone in Gaza City is risking their life,” said Israel’s defence minister, Yoav Gallant. Israeli military spokespeople on Sunday once again presented what they described as evidence of Hamas tunnel entrances under several hospitals in the Gaza Strip, an allegation they have made repeatedly. IDF senior spokesperson Daniel Hagari showed a video that he claimed depicted an underground entrance from Sheikh Hamad hospital, which he said connected to Hamas tunnel networks as well as Hamas gunmen opening fire at Israeli forces from the hospital. He also alleged the existence of tunnels beneath the Indonesian hospital in Beit Lahia, northern Gaza, raising fears that Israel might be planning to target them.