Israel pounded Gaza City and its outskirts overnight, residents said Thursday, as the military announced the first steps in its push to the enclave's largest population center.
The newly approved plan authorizes the call-up of roughly 60,000 reservists, deepening fears the campaign will worsen the already catastrophic humanitarian crisis in the Gaza Strip.
"We are not waiting. We have begun the preliminary actions, and already now, IDF (army) troops are holding the outskirts of Gaza City," said the Israeli military.
Israel's plans to expand the fighting and seize Gaza City have sparked international outcry as well as domestic opposition. The Red Cross became the latest voice to condemn the plan on Thursday, calling it "intolerable."
Ahead of the offensive, the Israeli military said the call-up of the reservists would begin in early September, adding the second phase of the so-called operation "Gideon's Chariots" had begun.
Gaza City residents described relentless bombardments overnight.
"The house shakes with us all night long – the sound of explosions, artillery, warplanes, ambulances, and cries for help is killing us," one of them, Ahmad al-Shanti, told AFP.
"The sound is getting closer, but where would we go?"
Another resident, Amal Abdel-Aal, said she watched the heavy strikes on the area, a week after being displaced from her home in Gaza City's al-Sabra neighborhood.
"No one in Gaza has slept – not last night, not for a week. The artillery and airstrikes in the east never stop. The sky flashes all night long," she added.
Gaza civil defense agency spokesman Mahmud Bassal said airstrikes and artillery fire overnight targeted areas to the northwest and southeast of Gaza City.
The U.N. humanitarian agency, meanwhile, warned the Israeli plan to expand military operations in Gaza City would have "a horrific humanitarian impact" on the already exhausted population.
"Forcing hundreds of thousands to move south is a recipe for further disaster and could amount to forcible transfer," OCHA said.
The U.N. Human Rights office in the Palestinian territories also voiced concern.
"Hundreds of families have been forced to flee, including many children, persons with disabilities, and older people, with nowhere safe to go," it said.
Others reportedly "remain trapped, completely cut off from food, water and medicine supplies," it added.
As Israel tightened its grip on Gaza City's outskirts, meditators continued to wait for an official Israeli reaction to their latest ceasefire proposal that Hamas accepted earlier this week.
Earlier Thursday, U.N. Secretary-General Antonio Guterres urged an immediate cease-fire in Gaza after Israel announced the first steps of an operation to seize Gaza City.
"It is vital to reach immediately a cease-fire in Gaza," that was necessary "to avoid the death and destruction that a military operation against Gaza City would inevitably cause," Guterres said in Japan, where he is attending the Tokyo International Conference on African Development.
Guterres also called for the unconditional release of hostages held by Hamas. He also urged Israel to reverse a decision to expand "illegal" settlement construction in the West Bank.
The Israeli settlement plan, which would bisect the occupied West Bank and cut it off from East Jerusalem, was announced last week and received the final go-ahead from a Defense Ministry planning commission on Wednesday.
The Gaza war was triggered by the Oct. 7 Hamas incursion, which caused around 1,200 deaths and took over 200 hostages, according to Israeli figures.
Israel's genocidal war, in comparison, has killed over 62,000 Palestinians, according to the enclave's Health Ministry.
