Hamas committed war crimes. The Israel Gaza evacuation order risks more.

Last week, Hamas-led fighters crossed into Israel and massacred Israeli civilians, killing hundreds and taking scores hostage, including children, people with disabilities and older people. The militants ambushed partygoers at a rave, shot families and set fire to homes. Hamas and other armed groups in Gaza have indiscriminately fired thousands of rockets at Israeli towns, causing death and injury. Hamas has committed numerous war crimes, including the taking of hostages.

But war crimes by one party don’t justify war crimes by the other. On Friday, the Israeli army ordered more than 1 million people — half the population — to leave northern Gaza within 24 hours, in advance of an imminent military ground operation. Though that initial deadline passed, the order raises serious legal and humanitarian red flags — and fears for the safety of civilians.

In response to the Hamas-led attacks, Israeli authorities have conducted massive airstrikes on densely populated neighborhoods in Gaza that have killed more than 2,400 people. The Gaza Health Ministry said Saturday over 700 of the dead are children. Israel has cut food, fuel and electricity supplies to Gaza and blocked aid from entering. As the United Nations has stated, such measures amount to a form of collective punishment, which is a war crime and prohibited by the Fourth Geneva Convention.

While Israeli forces say their airstrikes target Hamas assets, dropping explosive weapons on densely populated areas causes foreseeable significant harm to civilians and raises the risk of unlawfully indiscriminate attacks. More than 2.2 million people live in the Gaza Strip, which is about the physical size of Philadelphia. Children make up almost half the population. The area has been mostly closed off to the outside world by fences, walls and the Israeli navy, which patrols Gaza’s waters.

If evacuating more than a million people in a densely populated area weren’t hard enough, the Gaza Strip’s crossings with Egypt and Israel are closed, so moving to the overcrowded homes of relatives and friends in southern Gaza is currently the only option. The roads are strewn with rubble. Fuel is scarce. For many older people, people with disabilities and hospital patients, evacuation is impossible.

At least tens of thousands of people have fled northern Gaza, using the routes designated by the Israeli military, but airstrikes and rockets continue without pause. Already, 70 people, mostly women and children, were killed as they evacuated, according to the Palestinian Health Ministry. Gaza’s main Al-Shifa Hospital is struggling to treat the bulk of the over 9,000 Palestinians injured thus far, and evacuating its patients is not an option.

International humanitarian law, or the laws of war, lay out obligations that parties to a conflict owe to civilians, no matter what the other side does. The fact that Hamas-led fighters targeted civilians doesn’t allow the Israeli military to target civilians or flout its obligations to protect them.

The evacuation order creates at least three concerns under international humanitarian law.

First, parties to a conflict should issue effective warnings to civilians, where such warnings can help them avoid harm. But alerting civilians to flee, when there’s no safe place to go and no way to get there safely, neither suffices nor actually protects them. Civilians who remain in place after a warning to evacuate — including those who fear the dangerous journey to the south and the conditions they’ll find there — do not lose the protections of international humanitarian law. No matter what impossible choices families in Gaza make — the Israeli military is obligated never to target civilians or civilian infrastructure and to take all measures to minimize harm to civilians and civilian facilities such as homes, schools and hospitals.

Second, the laws of war prohibit “threats of violence the primary purpose of which is to spread terror among the civilian population.” Calls to evacuate that are not genuine warnings but rather primarily intended to cause panic among residents, or compel them to leave their homes for reasons other than their safety, are prohibited. The sweeping nature of the Israeli government’s order and the impossibility of safe compliance raise concerns that the purpose is not to protect civilians, but rather to terrify them into leaving their homes. An Israel Defense Forces spokesman’s statement that those who evacuated northern Gaza were “doing the clever thing” heightens concerns about how Israeli forces will treat the civilians who stay put.

Third, the order risks forced displacement, which is a war crime. About 70% of Gaza residents are refugees who fled their homes in what is now Israel in 1948, and their descendants. Many of the older people in northern Gaza remember all too well their flight from the Israeli army 75 years ago — and Israel’s subsequent refusal to allow them to return. Statements by Israeli officials calling on Gaza residents to flee to Egypt exacerbate the fears of many Palestinian refugees in Gaza that they will lose their homes once again.

U.N. Secretary-General António Guterres has said that ordering hundreds of thousands of people to evacuate on short notice, when there’s no safe place to go, will have devastating humanitarian consequences. International and humanitarian agencies agree.

The U.S. government, which provides $3.8 billion in annual military aid to Israel, should urgently insist that the Israeli government cancel the order, allow humanitarian aid into Gaza and fulfill its other obligations to protect civilians, including those who remain in northern Gaza. No matter what Hamas has done, there is no justification for stripping civilians in Gaza of the protections that the laws of war provide.