Dozens of Palestinians were killed or injured in an Israeli strike on a multi-story residential building in northern Gaza's Beit Lahiya on Sunday, medics told Reuters.
There was no immediate figure for how many people were killed. The Palestinian Civil Emergency said around 70 people have lived in the property.
The Hamas-run Gaza government media office put the number of those killed at 72, saying the strike hit a residential building that housed members of six families.
There was no immediate comment from Israel.
The Israeli army sent tanks into Beit Lahiya and the nearby towns of Beit Hanoun and Jabalia, the largest of the Gaza Strip's eight historic refugee camps, last month in what it said was a campaign to fight Hamas militants waging attacks and prevent them from regrouping.
It said it has killed hundreds of militants in those three areas, which residents said Israeli forces had isolated from Gaza City.
Earlier on Sunday, an Israeli airstrike killed at least 10 people in the Bureij camp in the central Gaza Strip, when a missile hit a house, medics said.
Four other people were killed in the nearby Nuseirat camp, they added.
The Gaza health ministry said 43,799 people have been confirmed dead since Oct. 7, 2023. Hamas militants killed around 1,200 Israelis that day, and still hold dozens of some 250 hostages they took back to Gaza, according to Israeli tallies.