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Relatives of a Palestinian killed in an Israeli attack mourn in Khan Younis, southern Gaza Strip, on July 10.Hatem Khaled/Reuters

Israeli airstrikes killed 20 Palestinians, including six children and three women, in central Gaza early Wednesday morning, some of whom were in a so-called “safe zone” declared by the Israeli military, hospital officials said.

This second straight night of deadly attacks on the central city of Deir al-Balah and nearby refugee camps came as U.S., Egyptian and Qatari mediators, as well as Israeli officials, met in the Qatari capital Doha to discuss a long-awaited ceasefire and hostage release deal.

Israel and Hamas appear to have closed the gap in recent days, but obstacles remain.

Attacks on Wednesday morning hit three homes in the Nuseirat refugee camp, killing 12 people, including five children, officials at the al-Aqsa Martyrs Hospital, where the victims were taken, said. An Associated Press reporter counted the bodies.

The camp, like others around Gaza, was originally established to house Palestinians displaced from their homes during the 1948 war surrounding the creation of Israel. It has grown into an urban neighborhood in the decades since.

A fourth attack early on Wednesday killed four men, three women and a child when it struck a house in Deir al-Balah, an area within the “humanitarian safe zone” where Israel has ordered Palestinians to seek refuge as it carries out offensives in several parts of the Gaza Strip.

The overnight bombing came hours after Israeli warplanes struck the entrance to a school housing displaced families outside the southern town of Khan Younis. The death toll from the attack rose to 31 dead, including eight children, and more than 50 wounded, officials at the nearby Nasser Hospital said Wednesday.

Footage broadcast by Al-Jazeera television showed children playing football in the schoolyard. When the area was suddenly startled by a bang, shouts of “Strike, strike!” could be heard.

The Israeli military said it was investigating the airstrike on the school and reports of civilian casualties, and claimed it targeted a Hamas militant who took part in the Oct. 7 attack on Israel, although it provided no direct evidence. The military blames Hamas for the civilian deaths because the militants fight in densely populated, urban areas. But the military rarely comments on the targets of individual strikes, which often kill women and children.

In nine months of bombardments and offensives in Gaza, Israel has killed more than 38,200 people and wounded more than 88,000, according to the territory’s Health Ministry, which does not distinguish between fighters and civilians in its count. Nearly the entire population has been forced from their homes. Many have been displaced multiple times. Hundreds of thousands are huddled in sweltering tent camps.

The Israeli attack was triggered by Hamas’s cross-border raid on Oct. 7, in which militants killed 1,200 people in southern Israel, most of them civilians, according to Israeli authorities. The militants took about 250 hostages. About 120 remain in captivity, with about a third believed to be dead.

This week, Israeli forces also launched a new ground assault on Gaza City in the northern part of the territory, the latest effort to combat Hamas militants who have regrouped in areas the army previously said had been largely cleared.

Large parts of Gaza City and the surrounding urban areas were flattened or left a devastated landscape by previous Israeli attacks, and much of the population fled earlier in the war. But the latest incursions and bombardments have led to a new flight of people.

After Israel called for evacuations from eastern and central Gaza City on Monday, staff at two hospitals – Al-Ahli and the Patients Friends Association Hospital – rushed to transfer patients and closed their doors, the United Nations said.

The Israeli military said Tuesday it had told hospitals and other medical facilities in Gaza City that they did not need to evacuate. But hospitals in Gaza have often closed and transferred patients at any sign of possible Israeli military action, fearing incursions.

In the past nine months, Israeli forces have attacked at least eight hospitals, resulting in the deaths of patients and medical personnel, as well as massive destruction of facilities and equipment. Israel has alleged that Hamas uses hospitals for military purposes, although it has provided only limited evidence.

According to the United Nations humanitarian agency, only 13 of Gaza’s 36 hospitals are operational, and only partially so.

International mediators made a new concerted effort to push through a proposed ceasefire.

An Egyptian official said the head of Egypt’s General Intelligence Service, Abbas Kamel, was traveling to Doha to participate in the deal talks. The official said U.S. and Israeli officials were also present. The official spoke on condition of anonymity because he was not authorized to brief the press on the meetings.

A day earlier, CIA Director William Burns, who led the U.S. mediation, met with Egyptian President Abdel Fattah el-Sissi in Cairo. There are still obstacles in the talks, even after Hamas agreed to abandon its main demand that Israel commit to ending the war as part of any deal. Hamas still wants mediators to guarantee that the negotiations will end with a permanent ceasefire.

Israel has rejected any deal that would force it to end the war with Hamas intact. Hamas accused Israeli Prime Minister Benjamin Netanyahu on Monday of “putting more obstacles in the way of negotiations,” including operations in Gaza City.

At least 20 people were killed and more than 50 wounded in a major Russian missile attack in Ukraine on Monday, authorities said. One of the missiles hit a major children’s hospital in the capital Kiev, where emergency services were searching for victims.

The Associated Press