Palestinians continued to flee northern Gaza on Saturday, a day after the Israeli military ordered all civilians in that region – which has a population of about 1.1 million – to evacuate within 24 hours.

Families moved along an arterial road away from Gaza City in cars, trucks and donkey carts, carrying along their possessions, the Associated Press reported.

On Friday, the Israeli military ordered civilians in Gaza City to move to areas south of Wadi Gaza, which is the southern boundary of the city. It said they should only return when the military makes another announcement allowing them back.

The Israeli Defense Forces have alleged that Hamas militants are hiding in Gaza in tunnels underneath houses and inside buildings populated by innocent civilians. They have also alleged that the militant group is using civilians as human shields.

This comes six days after an unprecedented cross-border assault on Israel by Hamas militants. In response to Hamas’ assault, Israel declared a siege of Gaza on Monday and launched a series of airstrikes ahead of a reportedly imminent ground operation. It also stopped water, fuel and power supplies to Gaza.

As of Saturday, more than 2,200 people have been killed in Gaza. The Hamas’ assault had killed over 1,300 Israelis. Additionally, the bodies of around 1,500 Hamas militants have been found inside Israeli territory since the conflict began, authorities in Israel said.

The Israeli military said that Hamas is holding over 120 civilians captive in Gaza.

On Saturday, United Nations Secretary-General António Guterres reiterated the need for human rights to be respected. “Even wars have rules,” Guterres said. “International humanitarian law and human rights law must be respected and upheld. Civilians must be protected and also never used as shields. All hostages in Gaza must be released immediately.”

Late on Friday, the Israeli military renewed calls on social media for civilians in Gaza to move south. “Now Hamas is hiding behind the people in Gaza,” it said. “That’s why we’re asking them to move.”

It also dropped leaflets from the air into Gaza ordering people to leave the northern part of the region.

Israeli forces conducted localised raids in Gaza on Friday to look for abducted civilians. The military said the ground troops left after the raids.

‘Impossible to evacuate vulnerable hospital patients’, says WHO

The World Health Organization on Friday called for the “immediate reversal” of the Israeli military’s order so that health facilities can continue to function in northern Gaza.

“The Palestinian Ministry of Health has informed WHO that it is impossible to evacuate vulnerable hospital patients without endangering their lives,” the organisation said. “Vulnerable patients include those who are critically injured or dependent on life support. Moving them amid hostilities puts their lives at immediate risk.”

It also said that the hospitals in southern Gaza were already functioning “at or beyond capacity” and cannot treat additional patients.

‘Fully prepared’ to join the fight, says Hezbollah

Lebanon-based militant group Hezbollah, which is backed by Iran, said on Friday that it will be “fully prepared” to join its ally Hamas in the fight against Israel when the time is right.

“We, as Hezbollah, are contributing to the confrontation and will [continue] to contribute to it within our vision and plan,” Hezbollah deputy chief Naim Qassem said at a pro-Palestinian rally in Lebanon. “We are fully prepared, and when the time comes for action, we will take it.”