JERUSALEM — Israel said Saturday it has launched a major operation in the Gaza Strip to pressure Hamas to release remaining hostages, following days of strikes across the Palestinian territory that killed hundreds of people.

Defense Minister Israel Katz said Operation Gideon Chariots was being led with “great force.” Prime Minister Benjamin Netanyahu had vowed to escalate pressure with the aim of destroying the militant group that has ruled Gaza for nearly two decades.

The military operation came a day after U.S. President Donald Trump concluded his Middle East trip without a visit to Israel. There had been hope that Trump’s trip could increase the chances of a ceasefire deal or the resumption of humanitarian aid to Gaza, which Israel has prevented for more than two months.

Negotiations between Israel and Hamas have yet to achieve progress in Qatar’s capital, Doha. Hamas, which released an Israeli American hostage as a goodwill gesture before Trump’s trip, insists on a deal that ends the war and leads to the withdrawal of Israeli forces — something Israel said that it won’t agree to.

Israel’s army said on social media that it was intensifying attacks and exerting “tremendous pressure” on Hamas across Gaza, and wouldn’t stop until the hostages are returned and the militant group is dismantled.

Israel believes as many as 23 of the hostages in Gaza are still alive, although Israeli authorities have expressed concern for the status of three of them.

More than 150 people in Gaza had been killed in Israeli strikes in the previous 24 hours, Gaza’s Health Ministry said Saturday. It said more than 3,000 have been killed since Israel broke a January ceasefire on March 18.

“This is unacceptable. Until when? Until we all die?” asked a sweating Naji Awaisa as he and others fled one of the targeted areas, the Jabaliya refugee camp, with their belongings down streets lined with shattered buildings. Smoke from airstrikes rose in the distance.

There was no immediate Israeli comment on the strikes. A separate statement said that the military had killed dozens of fighters while dismantling an “underground route” in northern Gaza.

Hundreds of protesters rallied Saturday night in Tel Aviv, some holding photos of Palestinian children killed in Gaza, with others demanding a deal to end the war and bring all hostages home.

Gaza is in the third month of an Israeli blockade with no food, water, fuel or other goods entering the territory. Food security experts say Gaza will be in famine if the blockade isn’t lifted.

Last week, a new humanitarian organization that has U.S. backing said it expects to take over aid delivery by the end of the month, after what it described as key agreements with Israeli officials.

Many in the humanitarian community, including the U.N., said that they won’t participate, because the system doesn’t align with humanitarian principles and won’t be able to meet the needs of Palestinians in Gaza.