Eight Israeli soldiers were killed in a blast in southern Gaza, the Israeli military said on Saturday.
It gave no details of the circumstances of the incident but earlier the armed wing of Hamas said it had killed and wounded a number of Israeli soldiers in an ambush on an armoured personnel carrier in the southern city of Rafah.
Israeli tanks advanced in Tel Al-Sultan and shells landed in the coastal area, where thousands of Palestinians, many of them displaced several times already, have sought refuge.
Despite growing international pressure for a ceasefire, an agreement to halt the fighting still appears distant, more than eight months since the start of the war in October.
In Israeli air strikes on two houses in Gaza City suburbs, residents said at least 15 people were killed. Four others were killed in separate attacks in the south, medics said.
The Islamic Jihad armed wing, Al-Quds Brigades, said on Saturday Israel could only regain its hostages in Gaza if it ended the war and pulled out forces from the enclave.
A spokesman for Al-Quds Brigades made the remarks in a video posted on Telegram.
Islamic Jihad is a smaller ally of Hamas, which led a rampage in southern Israel on Oct. 7 in which 1,200 people were killed and more than 250 taken hostage, according to Israeli tallies. More than 100 hostages are believed to remain captive in Gaza, although at least 40 have been declared dead in absentia by Israeli authorities.
Since a week-long truce in November, repeated attempts to arrange a ceasefire have failed, with Hamas insisting on a permanent end to the war and full Israeli withdrawal from Gaza. Israel's Prime Minister Benjamin Netanyahu refuses to end the war before Hamas is eradicated.
At least 37,296 Palestinians, at least 30 of them in the past 24 hours, have been killed in Israel's military campaign to eliminate Hamas, according to the Gaza health ministry.
