DEIR AL-BALAH, Gaza Strip — An Israeli airstrike killed a prominent Palestinian doctor and eight members of his extended family on Tuesday after they complied with military orders to evacuate their home and moved into an Israeli-designated safe zone.

The Hamdan family — around a dozen people from three generations — fled their home in the middle of the night after the Israeli military ordered an evacuation from the southern Gaza city of Khan Younis.

They found refuge with extended relatives in a building further north, inside an Israeli-declared safe zone. But hours after they arrived, an Israeli airstrike on Tuesday afternoon hit their building in the town of Deir al-Balah, killing nine members of the family and three others.

In all, five children and three women were among the dead, according to hospital records and a relative who survived.

Related Story: Israeli Strike Kills Another Senior Hezbollah Commander as Diplomats Scramble ...

Mass Flight Triggered by Evacuation Order

Israel’s order on Monday for people to leave the eastern half of Khan Younis — the territory’s second-largest city — has triggered the third mass flight of Palestinians in as many months, throwing the population deeper into confusion, chaos and misery as they scramble once again to find safety.

About 250,000 people live in the area covered by the order, according to the United Nations. Many of them had just returned to their homes there after fleeing Israel’s invasion of Khan Younis earlier this year — or had just taken refuge there after escaping Israel’s offensive in the city of Rafah, further south.

The order also prompted a frantic flight from European General Hospital, Gaza’s second-largest hospital, located in the evacuation area. The facility shut down after staffers and more than 200 patients were evacuated overnight and on Tuesday, along with thousands of displaced who had sheltered on the hospital grounds, according to the staff and the International Committee of the Red Cross, which had a medical team there.

Related Story: Israel Orders Khan Younis Evacuation, Hinting at Southern Gaza Assault

Nowhere Safe

Up to 15 members of the Hamdan family fled their Khan Younis home and arrived late on Monday at their extended family’s building in Deir al-Balah, said Asmaa Salim, a relative who lived in the building.

The building was located inside the extended humanitarian zone that the Israeli military had declared when it began its offensive in Rafah in May, telling Palestinians to evacuate there for safety.

The strike came around 3 p.m. on Tuesday. Associated Press video shows an entire floor of the building gutted. “Almost everyone inside was martyred, only two or three survived,” Salim told the AP.

Related Story: Israel Releases 55 Palestinians It Had Detained from Gaza, Including Hospital ...

Flight from Khan Younis

Monday’s evacuation order suggested a new ground assault into Khan Younis could be coming though there was no immediate sign of one. Israeli forces waged a months-long offensive there earlier this year, battling Hamas militants and leaving large swaths of the southern city destroyed or heavily damaged.

Israel has repeatedly moved back into parts of the Gaza Strip it previously invaded to root out militants it said had regrouped — a sign of Hamas’ continued capabilities even after nearly nine months of war in Gaza.

Israel’s campaign has killed more than 37,900 Palestinians, the majority women and children, according to Gaza’s Health Ministry, which doesn’t distinguish combatants among its count. Israel launched its campaign after Hamas’ Oct. 7 attack in which militants killed some 1,200 people in southern Israel and took around 250 others hostage.

The Israeli military said Tuesday it estimates that some 1.8 million Palestinians are now in the humanitarian zone it declared, covering a stretch of about 14 kilometers (8.6 miles) along Gaza’s Mediterranean coast. Much of that area is now blanketed with tent camps that lack sanitation and medical facilities with limited access to aid, U.N. and humanitarian groups say. Families live amid mountains of trash and streams of water contaminated by sewage.

Magdy and Keath reported from Cairo. Associated Press writer Sarah El Deeb in Beirut contributed to this report.