GAZA — More than 400 Palestinians were killed, including children and women, on Tuesday after Israel launched extensive airstrikes, Palestinian medics say.

The death toll in Gaza has reached 404, the health ministry in the enclave said, adding that several people remain trapped under the rubble.

Another 562 people have been injured, the health ministry said.

Gaza Civil Defense spokesman, Mahmoud Basal, told CNN that “more than 130 children and many women” have been killed, including entire families.

“We are in front of a very difficult situation and our medical and civil defense efforts do not meet the needed scale of the catastrophe,” Basal said

The Israeli military said it was carrying out "extensive" strikes after talks to extend the ceasefire failed — it's the biggest wave of strikes since 19 January, when the ceasefire began.

Israel’s Ministry of Foreign Affairs said the decision to restart military operations in Gaza came after “Hamas rejected two concrete mediation proposals presented by the US president’s envoy, Steve Witkoff.”

In a statement on Tuesday, ministry spokesperson Oren Marmorstein said Israel had agreed to the two proposals, whereas Hamas did not.

“As of this morning, Israel is operating with full force against the Hamas terrorist organization in the Gaza Strip,” the statement said. “From this point forward, Israel will act against Hamas with increasing military intensity.”

Hamas spokesperson Abdul Latif Al-Qanou said earlier Tueday that the group adhered to “all the terms” of the truce the two sides reached in January and “was keen to consolidate it and move to the second phase, but the occupation refused.”

Gaza’s hospitals are “completely full” and struggling to treat wounded Palestinians flooding in following renewed Israeli strikes, the head of the enclave’s biggest hospital said.

“Our hospitals are unable to accommodate the increasing number of injured, as operating rooms are completely full, and the wounded are dying without finding a bed for treatment,” Muhammad Abu Salmiya, of Al-Shifa Hospital in Gaza City said in a post on X.

He said the attack had dealt a blow to “an exhausted healthcare system suffering from a shortage of medications and a severe lack of medical equipment.”

A doctor at another hospital previously told CNN she had personally pronounced between 15 to 20 people dead in scenes that were “nothing close to anything I’ve experienced before” and that the majority of patients she had seen were children.

Israel’s return to war in Gaza will inevitably worsen the already dire humanitarian situation in the Palestinian territory, a leading humanitarian organization warned on Tuesday.

Shaina Low, a communications adviser at the Norwegian Refugee Council (NRC), said her colleagues in Gaza were woken up by “intensive bombing” from Israeli attacks that continued until dawn.

“People, including our staff, are, of course, in shock. They are very stressed out. They are very worried about what is to come,” Low told CNN’s Rosemary Church from Jordan’s capital Amman.

Early Tuesday morning, Israel’s Prime Minister’s office said it instructed the army to target Hamas across the Gaza Strip.

The strikes were reported to have hit targets in northern Gaza, Gaza City, Deir al-Balah, Khan Younis, and Rafah.

The scale of the horror is "unimaginable", according to one volunteer with Medical Aid for Palestinians based at Nasser Hospital. Dr. Tanya Haj Hassan said she had personally treated at least five patients who died in the emergency room.

“The ER was just chaos, patients everywhere, on the floor,” she said. “There were probably three men, and the rest were all children, women, and the elderly—everybody caught in their sleep, still wrapped in blankets. Terrifying.”

The surprise attack broke a period of relative quiet during the Muslim holy month of Ramadan and increased fears that the 17-month conflict, which has claimed tens of thousands of Palestinian lives and left Gaza in ruins, would resume in full.

When the Israeli planes struck, Palestinians at a school in Gaza City that was providing shelter to displaced families reported being forcibly shaken out of their sleep.

More than two dozen people died, according to hospital officials.

“People are sleeping peacefully; they set the alarm to wake up for suhoor, and they wake up to death,” said Fedaa Heriz, a displaced woman, referring to the early morning meal during the fasting month of Ramadan.

“I heard screaming, my mother and sister screaming, calling for help. I came and entered the room and found the children under the rubble, under the stones,” said Majd Naser, a displaced Palestinian.

The Israeli military had no immediate comment on the school strike, which was part of a renewed offensive in Gaza.

The strikes come as the ceasefire between Hamas and Israel remains in limbo. The first stage of the three-phase deal brokered by the US, Qatar, and Egypt started mid-January and ended on the first of March.

Negotiations on the second phase have not yet been hammered out.

Hamas condemned the latest raids and said it holds Israeli Prime Minister Benjamin Netanyahu responsible for the "unprovoked escalation" against Palestinians.

"We hold the criminal Netanyahu fully responsible for the consequences of the treacherous aggression on Gaza, the defenseless civilians and our Palestinian people," the group said on Telegram.

Hamas warned the strikes breached the ceasefire and put the fate of the hostages in jeopardy.

"Netanyahu and his extremist government have decided to violate the ceasefire agreement and expose the prisoners in Gaza to an unknown fate," the statement said.

Meanwhile, the Hamas-run government media office in Gaza said at least four of its senior officials, including two top police officers, were killed in the Israeli strikes.

They named the officials as Issam al-Daalis, head of the government administrative committee; Maj. Gen. Mohamed Abu Watfa, undersecretary of the Interior Ministry, Maj. Gen. Bahgat Abu Sultan, director of the domestic security agency and Ahmed al-Hetta, undersecretary of the Justice Ministry.

Earlier on Monday, Israel launched attacks toward Gaza, southern Lebanon, and southern Syria, killing at least ten people, according to local authorities. — Agencies