A few minutes before 3 a.m. on Nov. 19, Khalid Azzam’s cellphone rang.

It was late for a call. But the number flashing on his phone’s screen — an Israeli number — raised concern. As a member of Islamic Jihad, Azzam was a target in Israel’s widening air campaign six days into its recent confrontation with the various armed groups of the Gaza Strip.

The Israel Defense Forces often call the militants in Gaza whose homes it intends to strike minutes before doing so, a way of minimizing the deaths of any women and children who might be inside.

For Israel, the warnings have a logic that is both moral and strategic. Even a successful operation against a senior militant can be overshadowed by the outrage — among Palestinians and around the world — that can ensue over civilian deaths.

But the phone calls are no guarantee that innocents will be spared. No single event ­galvanizes support for Gaza’s armed groups like mass civilian killings by Israel’s military, and despite what Israel describes as exceptional caution, the recent conflict featured several of them.

On the night of the 19th, Azzam did not answer his phone, according to several family members who recounted the incident this week. Moments later, when the buzz of an Israeli drone sounded above his family home in the Zeitun neighborhood, Azzam gathered the dozen people who were inside and fled into the street.

Within minutes, a drone strike, followed by an Israeli military jet’s bombing run, demolished the Azzam home and at least four others around it. Among them were two that belonged to the Abu Zor family, whose members say they had no affiliation with Gaza’s armed groups, chief among them Hamas. Two young mothers, Sahar and Nisma Abu Zor, and a 3-year-old named Mohammed perished in a blast meant to kill someone else.

“We were blown into the streets,” said Hana Abu Zor, Mohammed’s grandmother. “The house just came down around us.”

The details and aftermath of the airstrikes in Zeitun show how Israel, even while attempting to avoid civilian casualties, plays into the hands of its enemies in the cramped conflict here. Although there is lingering anger toward the Azzams, who say they did not have enough time to warn their neighbors before the attack, the survivors ultimately blame Israel.

Meanwhile, Hamas, which faced rising public discontent before the eight-day confrontation with Israel, has reaped benefits from such attacks and has emerged in perhaps its strongest political position since taking full control of the Mediterranean enclave five years ago.

Embedded among civilians

Of the 174 Palestinians killed in the conflict, 43 percent were women, children and seniors, according to the Palestinian Ministry of Health. More than half of the 1,400 people wounded fall into the same categories.

Hamas and the other armed groups in Gaza use their arsenals to kill as many Israelis, and sow as much terror, as possible. During the conflict, Gazan militants fired more than 1,500 rockets into Israel’s towns and cities, killing four Israeli civilians and two soldiers. Their ordnance is far less powerful than Israel’s. But as the range of Hamas’s rockets has increased since the last outbreak of violence nearly four years ago, so has the arc of fear, which now stretches nearly to Jerusalem.

Hamas’s leaders argue that because nearly all Israelis serve in the military, none are civilians. It is an argument that defies the laws of war.

Israel has a different challenge. Behind its military operations and years-long blockade of the Gaza Strip is an ambition to stir popular resentment against Hamas, in a bid to turn the territory’s 1.7 million residents against the Islamist movement. This is a goal that every civilian death here during an Israeli military operation works against, sometimes with assistance from Hamas.

In past conflicts, Hamas and the smaller armed groups in Gaza, including Islamic Jihad, have intentionally fired rockets from residential areas so the risk of civilian deaths will make Israeli reprisals more complicated.

Although Hamas’s security forces are sometimes stationed in urban bases and rural outposts across the strip during times of calm, they do not remain there during conflict. Foot soldiers in Gaza’s armed groups commonly live in crowded neighborhoods surrounded by civilians, as was the case along the Abu Zor family’s small street in Zeitun.

Within days of the Israeli airstrikes, Hamas activists strung banners in front of the Abu Zor family’s ruined homes. Each expressed condolences for the deaths of Sahar, Nisma and Mohammed Abu Zor, who was born during the last Gaza war and died in this conflict.

Another banner expressed the same sentiment for Ahad Qutati, who lived across the narrow street and once worked construction inside Israel. In addition, Hamas officials handed out about $1,000 each to the Azzam, Abu Zor and Qutati families, “emergency money” to help pay medical bills, buy food and rent new places to live.

“We are not Hamas,” said Majid Qutati, the younger brother of Ahad. “But we also feel proud after this war, despite the pain. We feel now the resistance is powerful, and when Israel hits civilians, they provoke all of us.”

The Abu Zors and Qutatis had been living for years as neighbors in Zeitun, a crowded series of three- and four-story concrete-block homes filled with extended Palestinian families on the ragged eastern outskirts of Gaza City.

Family members said they didn’t know that another neighboring family, the Azzams, included a member of Islamic Jihad. Mohammed Qutati, an engineering student at al-Azhar University whose uncle Ahad died in the airstrikes, said, “If we had known, we would have left.”

The neighborhood’s mostly dirt streets have turned muddy with recent rain, and in a clear blue sky a week after the bombing, an Israeli military jet sketched loops in vapor trails that captivated many in Zeitun as they took small steps to reassemble their lives.

Fear and grief

Hours before the airstrikes, Nisma Abu Zor, fearful of the steady Israeli bombardment of the city, put on a prayer shawl and told her husband, Saadi, “Maybe tonight I will die.”

Just before 3 a.m., as the couple struggled to sleep, they heard the telltale buzz of an Israeli drone over the neighborhood. Its target was the Azzam home, just a few feet behind their own. Unbeknown to the Abu Zors, the Azzams were quickly leaving after the IDF warning call.

The IDF declined to comment on the incident. But a spokesman confirmed that the military often calls militants or sends text messages before hitting a home to keep civilian deaths as low as possible.

Several members of the Abu Zor family described a quick succession of blasts soon after the drone arrived, including one that crashed through the roof of Fuad Abu Zor’s home. Nisma helped wake her two children and headed downstairs when another explosion threw her against a wall, nearly knocking her out.

Mohammed, the 3-year-old, had received a fatal wound in the leg by the time his father, Iyad, managed to carry him to his uncle Mohammed’s home. They were among 34 members of the family who huddled inside a place that they thought offered some refuge.

Within minutes, a far larger blast blew out the walls of the house. Many of those inside — including Nisma, 20, and Sahar, 19 — were blown across the street. They lay in the rubble in front of the Qutati home.

There, Ahad Qutati, who had come outside to help with the frantic evacuation from one home to another, was killed by shrapnel that pocked the front of his house. A poster of his face now hangs in the place he died, next to his brother Majid’s crushed taxi.

“His wife had begged him not to go outside once he heard the screams,” said Mohammed Qutati, Ahad’s nephew. “But he told her, ‘If I can help, I must.’ ”

Ambulances rushed to the scene from al-Shifa Hospital, a 15-minute drive away. Soon, the bodies of Nisma, Sahar and little Mohammed were carried in, filmed by journalists staking out the emergency room.

Tahanni Abu Zor watched in confused grief. Streaks of blood lined her face, and the area around her eyes, pitted with glass shards, was distorted by swelling and cuts.

But she refused treatment, asking only after Sahar, her dying daughter-in-law, and her 10-year-old son, also named Mohammed.

A week after the blast, he was taken from the hospital’s intensive care unit, his head still swathed in bandages. A British charity called Islamic Help placed a large box of chocolates at his side and a $50 bill in his hands.

Mohammed has yet to speak. His mother, Tahanni, has not seen him for days.

She has been busy looking for a home to rent for her family, eventually finding one on the edge of Zeitun with the money Hamas provided. In her arms, nearly round the clock, squirms Shahad, the 2-year-old daughter of Sahar.

Shahad continues to ask for her mother.

The Azzam family has visited the Abu Zors since the airstrikes, offering condolences and apologies. Picking through the debris of the family home this week, Anwar Azzam, a lawyer, said his 27-year-old cousin Khalid escaped uninjured and is in hiding.

But Tahanni Abu Zor does not blame the Azzams.

“It’s fate, only fate, that brought us here,” she said, sitting among the parched olive trees outside the family’s rented home. “Even if we get any help now to rebuild, the Israelis will be back in three or four years, and we will face the same thing again.”