As Israel Defense Forces bombing continued to kill and maim large numbers of Palestinians across the Gaza Strip over the weekend and into Monday, the discovery of the bodies of medical workers who were apparently executed by their captors and the publication of several reports in which Israeli soldiers admit to torturing prisoners and using civilians as human shields have drawn renewed war crimes accusations and calls for accountability.

On Sunday, the Palestine Red Crescent Society (PRCS) said it had recovered the bodies of 15 Palestinian first responders from a mass grave, including eight Red Crescent workers and six Civil Defense personnel, who were killed by Israeli forces on March 23 while traveling "on duty" in five ambulances, a fire truck, and a United Nations vehicle in the al-Hashashin area of southern Gaza.

Jonathan Whittall, head of the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) in Gaza, said Sunday that the vehicles were picked off "one by one."

"Their bodies were gathered and buried in this mass grave," Whittall added. "We're digging them out with uniforms, with their gloves on. They were here to save lives. Instead, they ended up in a mass grave."

The Gaza Health Ministry said that "some of these bodies were bound and shot in the chest" before being "buried in a deep hole to prevent their identification."

Accusing Israel of a "heinous crime," the ministry called on U.N. agencies "and relevant international bodies to conduct an urgent investigation into these crimes and hold the occupation accountable for committing them."

An Israel Defense Forces (IDF) spokesperson said troops opened fire on the convoy because it was "advancing suspiciously" toward their position.

"Following an initial assessment, it was determined that the forces had eliminated a Hamas military operative, Mohammad Amin Ibrahim Shubaki, who took part in the October 7 massacre, along with eight other terrorists from Hamas and the Islamic Jihad," the spokesperson claimed.

Israeli officials routinely claim – often with little or no evidence – that Palestinian first responders, United Nations workers, journalists, and other civilians that it kills are members of Hamas or other militant resistance groups.

The International Federation of Red Cross and Red Crescent Societies (IFRC) said in a statement Sunday that it is "outraged" by the killings, which it called "the single most deadly attack on Red Cross Red Crescent workers anywhere in the world since 2017."