By Nidal al-Mughrabi

CAIRO (Reuters) -Israeli military strikes killed at least 80 Palestinians across the Gaza Strip on Wednesday, local health authorities said, in an intensification of the bombardment as U.S. President Donald Trump visits the Middle East.

Medics said most of the dead, including women and children, were killed in a barrage of Israeli airstrikes on houses in the Jabalia area of northern Gaza.

Later on Wednesday, the Israeli military issued new evacuation orders to people in several districts in Gaza City, forcing thousands of Palestinians to leave their shelters.

The areas threatened by the evacuation warnings included several schools and the largest Shifa Hospital, according to a map published by the Israeli army.

Witnesses and medics said shortly after the evacuation orders Israeli planes carried several airstrikes against targets within Gaza City.

"Some victims are still on the road and under the rubble where rescue and civil emergency teams can't reach (them)," the health ministry statement said.

Israel's military had no immediate comment. It said it was trying to verify the reports.

Reuters television footage showed residents returning to the ruins of their homes. Some sifted through the remains of walls and furniture, looking for documents and belongings.

"They fired two rockets, they told us the house of Moqbel (had been hit)," said Hadi Moqbel, who lost relatives in the attack in Jabalia. "We came running, we saw body parts on the ground, children killed, the woman killed and a baby killed - his head was exploded like a flower. He was two months old."

Israeli press reports on Wednesday cited security officials as saying they believed Hamas military leader Mohammad Sinwar and other senior officials had been killed in a strike on Tuesday on what the Israeli military described as a command and control bunker under the European Hospital in the southern Gaza city of Khan Younis.

There was no confirmation by the Israeli military or Hamas. On Wednesday, witnesses and medics said an Israeli airstrike hit a bulldozer that approached the area of the strike at the European Hospital, wounding several people.

Late on Tuesday, Islamic Jihad, an Iranian-backed militant group allied with Hamas, fired rockets from Gaza towards Israel. Shortly before Israel hit back, its military issued evacuation orders to residents in the area of Jabalia and nearby Beit Lahiya.

TRUMP VISIT

Palestinians hope Trump's visit to Saudi Arabia, Qatar and the United Arab Emirates will provide pressure for a reduction of violence. Hamas on Monday released Edan Alexander, the last known living American hostage it had been holding.

Trump said in Riyadh on Tuesday that more hostages would follow Alexander and that the people of Gaza deserved a better future. He is not visiting Israel during his Middle East trip.

Ceasefire efforts have faltered. Hamas talked to the United States and Egyptian and Qatari mediators to arrange Alexander's release, and Israel has sent a team to Doha to begin a new round of talks.

On Tuesday, Trump's special envoys Steve Witkoff and Adam Boehler met hostage families in Tel Aviv and said they saw a better chance of an agreement for the hostages' release following the deal over Alexander.

Hamas said on Wednesday the continued attacks indicated that Israeli Prime Minister Benjamin Netanyahu wanted to "escalate the aggression and massacres against civilians to undermine those (ceasefire) efforts". Israel has blamed Hamas for the continuing war.

The U.S. has presented a plan to reopen humanitarian aid deliveries in Gaza using private contractors. Israel, which imposed a total blockade of supplies going into Gaza from March 2, has endorsed the plan but it has been rejected by the United Nations and international aid agencies.

Israel invaded Gaza in retaliation for the Hamas-led attack on southern Israeli communities on October 7, 2023, in which about 1,200 people were killed and 251 were taken as hostages to Gaza, according to Israeli tallies.

Israel's military campaign has killed more than 52,900 Palestinians, according to local health officials. It has left Gaza on the brink of famine, aid groups and international agencies say.

(Reporting and writing by Nidal al-Mughrabi. Additional reporting by Mahmoud Issa in Gaza; Editing by Aidan Lewis, Timothy Heritage and Diane Craft)