Israel killed at least 40 Gazans and wounded 60 others in overnight airstrikes on a tent camp at a designated humanitarian zone in the enclave, local emergency services said Tuesday.
With dozens of people missing, rescue workers continued their searches at the tent encampment near Khan Younis in the Al-Mawasi area, which Israel has designated a humanitarian safe zone for displaced Palestinians.
Witnesses said the camp, crowded with internally displaced families, was struck by at least four missiles.
The Gaza civil emergency service said at least 20 tents caught fire and missiles caused craters as deep as 9 meters (30 feet).
It said the 65 victims included women and children but did not immediately provide a breakdown of deaths and injuries.
There was no immediate comment from the Gaza Health Ministry, which compiles casualty figures. Earlier, the Hamas-aligned Shehab News Agency said 40 Palestinians were killed.
"Our teams are still moving out martyrs and wounded from the targeted area. It looks like a new Israeli massacre," a Gaza civil emergency official said.
The official added that teams had been struggling to search for victims who might have been buried.
The Israeli military said it "struck significant Hamas ... operating within a command and control center embedded inside the Humanitarian Area in Khan Younis."
Palestinian resistance members allegedly advanced and carried out attacks against IDF troops and Israel, the Israeli Defence Forces claimed.
Hamas denied Israeli allegations that gunmen were present in the targeted area and rejected accusations it exploited civilian areas for military purposes.
"This is a clear lie that aims to justify these ugly crimes. The resistance has denied several times that any of its members exist within civilian gatherings or use these places for military purposes," said Hamas in a statement.
Ambulances raced between the tent camp and a nearby hospital, while Israeli jets could still be heard overhead, residents said.
Nearly all of Gaza's 2.3 million people have been forced from their homes at least once, and some have had to flee as many as 10 times.
The war was triggered by the Oct. 7 Hamas incursion, causing around 1,200 deaths and taking about 250 hostages, according to Israeli tallies.
Israel's genocidal war on Gaza, in comparison, has killed more than 40,900 Palestinians, according to the local Health Ministry.
The two warring sides each blame the other for a failure so far to reach a ceasefire that would end the fighting and see the release of hostages.
