Israeli forces have killed nine Palestinians during a raid in the north of the occupied West Bank in the deadliest single day in the territory in years, prompting Palestinian leaders to cut security ties with Israel and leaving international mediators scrambling to prevent the violence from escalating. A 61-year-old woman and a male civilian were among the dead, the Palestinian health ministry said, and about 20 more people were seriously injured in the violence on Thursday morning. Two of the casualties were claimed by the militant group Palestinian Islamic Jihad, another four by Hamas, and one by the armed wing of the Palestinian president Mahmoud Abbas’s Fatah faction. The Palestinian Authority, which governs parts of the West Bank and works alongside Israel to contain militant activity, announced on Thursday night it was suspending security cooperation with the Israeli government – a step it has taken on a temporary basis in the past. Israel Defence Forces (IDF) soldiers arrived at daybreak at several entrances of the Jenin refugee camp, a militant stronghold in the north of the Palestinian territory, said Sakir Khader, a Palestinian-Dutch film-maker at the scene. Armed Palestinians shot at an Israeli armoured vehicle disguised as a commercial van, at which point the IDF returned fire and a fierce four-hour gun battle ensued, causing widespread damage, he said. “I was stuck in the middle of the firefight for hours,” Khader said. “It was crazy. There were snipers and drones and they used a bulldozer to block off a street. It destroyed lots of cars and a public meeting spot. “At the hospital there are mothers looking for their sons … Everything is still very tense. I have been coming to Palestine all my life and I have never seen something like this.” “The situation in Jenin camp is very critical,” the Palestinian health minister, Mai al-Kaila, said in a statement. Israeli forces had prevented ambulances from reaching the injured, she added. The raid’s death toll is the highest in a single operation ever recorded by the United Nations since the international body’s records began in 2005. UN and Arab mediators said on Thursday afternoon that negotiations were being held with Israel and Palestinian factions across the West Bank and Gaza Strip in an effort to calm the situation. Israel did not give any immediate indication it was engaged in talks. The defence minister, Yoav Gallant, put forces in the occupied West Bank and on the Gaza frontier on heightened alert. The IDF said it conducted the unusual daytime operation, which ventured deep into the camp, because of intelligence suggesting a cell linked to Palestinian Islamic Jihad was planning to carry out imminent attacks against Israelis. The army also denied firing teargas at a nearby hospital after video emerged showing children in the paediatric ward choking and coughing. Teargas had probably wafted inside the hospital from the clashes nearby, it said. There were no Israeli casualties. Thursday’s bloodshed in Jenin is the latest development in Operation Breakwater, a nine-month-old Israeli military campaign that has targeted Palestinian factions in the northern West Bank city and nearby Nablus on a near-nightly basis. It was launched in response to a wave of Palestinian terrorist attacks last spring. The operation has contributed to the highest death toll in the occupied West Bank since the second intifada, or Palestinian uprising, concluded in 2005, with about 250 Palestinians and 30 Israelis killed last year, according to rights groups. Another 30 Palestinians, among them fighters and civilians, have been killed so far in 2023. As large funeral processions in Jenin got under way on Thursday afternoon, Abbas declared three days of mourning and ordered flags at half mast. A general strike was also declared across the occupied West Bank and Jerusalem, and by lunchtime hundreds of people had headed towards Israeli military checkpoints to protest. At the Beit El checkpoint near Ramallah, soldiers fired teargas at the demonstrators, some of whom threw stones and set fire to tyres. Three Palestinians in the area were reportedly shot and seriously injured, according to local media. “It is the same story again and again. The occupation does not stop killing us, so we will not stop resisting,” said Nour, a 22-year-old student who wrapped her face in a black and white keffiyeh to protect against the teargas. Tensions in the decades-long conflict have soared as a result of the escalating violence, and recent polling suggests that support for the dormant peace process has reached an all-time low on both sides. The recent election of the most rightwing government in Israeli history is expected to inflame an already volatile situation. Members of the new Israeli coalition have pledged to accelerate the building of Jewish settlements in the West Bank – a practice that negates the possibility of a two-state solution – and loosen the rules of engagement for soldiers and police.