Israeli airstrikes killed at least Palestinians across the Gaza Strip on Thursday, including 11 people in a tent encampment sheltering displaced families, medics said.
They said the 11 included women and children in the Al-Mawasi district, which was designated as a humanitarian zone for civilians earlier in the war between Israel and Gaza's ruling Hamas group, now in its 15th month.
The director general of Gaza's police department, Mahmoud Salah, and his aide, Hussam Shahwan, were killed in the strike, according to the Hamas-run Gaza interior ministry.
"By committing the crime of assassinating the director general of police in the Gaza Strip, the occupation is insisting on spreading chaos in the (enclave) and deepening the human suffering of citizens," it added in a statement.
The Israeli military said it had conducted an intelligence-based strike in Al-Mawasi, just west of the city of Khan Younis, and eliminated Shahwan, calling him the head of Hamas security forces in southern Gaza. It made no mention of Salah's death.
Other Israeli airstrikes killed at least 43 Palestinians, including six in the interior ministry headquarters in Khan Younis and others in north Gaza's Jabalia refugee camp, the Shati (Beach) camp and central Gaza's Maghazi camp.
Israel's military said it had targeted Hamas fighters who intelligence indicated were operating in a command and control center "embedded inside the Khan Younis municipality building in the Humanitarian Area".
"As the year begins, we got reports of yet another attack on Al-Mawasi with dozens of people killed, another reminder that there is no humanitarian zone let alone a safe zone (in Gaza)", Philippe Lazzarini, head of the UN agency for Palestinian refugees UNRWA, said in a post on X.
"Every day without a ceasefire will bring more tragedy."
Asked about Thursday's reported death toll, a spokesperson for the Israeli military said it followed international law in waging the war in Gaza and that it took "feasible precautions to mitigate civilian harm".
Later on Thursday, separate Israeli airstrikes killed at least four people on Jala Street in downtown Gaza City and two in its Zeitoun district, medics said.
The Israeli military has accused Gaza fighters of using built-up residential areas for cover. Hamas denies this.
Hamas' smaller ally Islamic Jihad said it fired rockets into the southern Israeli kibbutz of Holit near Gaza on Thursday. The Israeli military said it intercepted one projectile in the area that had crossed from southern Gaza.
Israel has killed more than 45,500 Palestinians in the war, according to Gaza's health ministry. Most of Gaza's 2.3 million people have been displaced and much of the tiny, heavily built-up coastal territory is in ruins.
The war was triggered by Hamas' Oct. 7, 2023 cross-border attack on southern Israel in which 1,200 people were killed and another 251 taken hostage to Gaza, according to Israeli tallies.