UN Secretary-General Antonio Guterres has condemned the Israeli military’s excessive use of force in its largest operation in two decades against the Jenin refugee camp in the occupied West Bank, according to Al Jazeera.

More than 100 civilians were injured, thousands were forced to flee their homes, schools and hospitals were damaged, and water and electricity networks were disrupted during the Israeli military operation, Guterres said on Thursday.

Guterres also said Israeli forces had prevented the injured from receiving medical care and stopped humanitarian workers from reaching those in need.

The UN chief reminded Israel that “as the occupying power, it has a responsibility to ensure that the civilian population is protected against all acts of violence.”

“Israel’s airstrikes and ground operations in a crowded refugee camp were the worst violence in the West Bank in many years, with a significant impact on civilians,” Guterres said.

“I once again call on Israel to abide by its obligations under international law,” he said. “The use of airstrikes is inconsistent with the conduct of law enforcement operations,” he said. “I understand Israel’s legitimate concerns with its security, but escalation is not the answer.”

At least 12 Palestinians were killed in the two-day raid on the refugee camp, which involved approximately 1,000 Israeli soldiers and was accompanied by air attacks and deliberate damage to civilian infrastructure such as roads, water and electricity supplies.

Israeli forces also attacked hospitals in Jenin, “severely damaging their operational capacity,” according to Physicians for Human Rights Israel (PHRI).

“Five civilians were injured as a result, including three in serious condition,” the organization said. “When hospitals are attacked, and their protected status is ignored, the resulting damage is severe,” it added.

The secretary general’s condemnation followed a statement by three UN independent human rights experts on Wednesday who said that the Israeli air attacks and ground actions in Jenin “amount to egregious violations of international law and standards on the use of force and may constitute a war crime. “

The experts on human rights in the Palestinian territory, on the rights of the internally displaced, and on violence against women and girls called for Israel to be held accountable for its illegal occupation and violent acts to perpetuate it.

Al Jazeera’s Gabriel Elizondo, reporting from the UN headquarters in New York, said the secretary general said that he was “deeply disturbed” by what had occurred in Jenin and that he “strongly condemns all acts of violence against civilians.”

“After his remarks, Guterres was asked if he believes the Israeli raid on Jenin constitutes a war crime. The secretary general refused to answer that question,” Elizondo said.