Israeli strikes in Gaza killed more than 200 people in 24 hours, Hamas-controlled authorities said Saturday.
The United States again pressed its ally Israel to do more to protect civilians.
Despite growing calls for restraint and for more aid to reach war-stricken Palestinians, Israel showed little sign of modulating its 11-week-old "Operation Swords of Iron" -- which aims to rout Hamas, reports AFP.
Fighting is now centred on Gaza City and the southern city of Khan Yunis, both considered strongholds of the Palestinian militant group that carried out bloody October 7 raids into Israel.
After reports of heavy Israeli shelling, grey and black smoke rose over the north of the coastal territory and in Khan Yunis.
The refugee camp-turned-city is the birthplace of Yahya Sinwar, Hamas' leader in Gaza and the man Israel holds most responsible for the October attacks.
The Israeli Army chief of staff, Herzi Halevi, visited troops on the ground in Khan Yunis, telling them that the operation had been "very impressive, truly very impressive, both the attack here and carrying out the operation in a secure manner".
Outside a morgue at the city's Nasser Hospital, grieving relatives prayed, wept and stared vacantly as they tried to process incalculable loss.
Hamas authorities said the death toll from this war has now surged beyond 20,000.
"This is a genocide," said resident Rafat Al Aydi.
Israel denies directly targeting civilians and says the war against Hamas is vital to ensure the October raids on farms, villages and kibbutzim that killed an estimated 1,140 people can never be repeated.
Bd-pratidin English/Lutful Hoque
