DEIR AL-BALAH, Gaza Strip >> Palestinians held funerals Monday for 15 medics and emergency responders killed by Israeli troops in southern Gaza, after their bodies and mangled ambulances were found buried in an impromptu mass grave, apparently plowed over by Israeli military bulldozers.

The Palestinian Red Crescent says the slain workers and their vehicles were clearly marked as medical and humanitarian personnel and accused Israeli troops of killing them “in cold blood.” The Israeli military says its troops opened fire on vehicles that approached them “suspiciously” without identification.

The dead included eight Red Crescent workers, six members of Gaza’s Civil Defense emergency unit and a staffer from UNRWA, the U.N.’s agency for Palestinians. The International Red Cross/Red Crescent said it was the deadliest attack on its personnel in eight years.

Since the war in Gaza began 18 months ago, Israel has killed more than 100 Civil Defense workers and more than 1,000 health workers, according to the U.N.

Missing for days

The emergency teams had been missing since March 23, when they went at around noon to retrieve casualties after Israeli forces launched an offensive into the Tel al-Sultan district of the southern city of Rafah.

The military had called for an evacuation of the area earlier that day, saying Hamas militants were operating there. Alerts by the Civil Defense at the time said displaced Palestinians sheltering in the area had been hit and a team that went to rescue them was “surrounded by Israeli troops.”

“The available information indicates that the first team was killed by Israeli forces on 23 March,” the U.N. said in a statement Sunday night.

Further emergency teams that went to rescue the first team were “struck one after another over several hours,” it said. All the teams went out during daylight hours, according to the Civil Defense.

The Israeli military said Sunday that on March 23, troops opened fire on vehicles that were “advancing suspiciously” toward them without emergency signals.

It said “an initial assessment” determined that the troops killed a Hamas operative named Mohammed Amin Shobaki and eight other militants. Israel has struck ambulances and other emergency vehicles in the past, accusing Hamas militants of using them for transportation.

However, none of the dead staffers from the Red Crescent and Civil Defense had that name, and no other bodies were reported found at the site, raising questions over the military’s suggestion that alleged militants were among the rescue workers.

The military did not respond to requests for the names of the other alleged militants killed or for comment on how the emergency workers came to be buried.

The U.N. on Monday demanded “justice and answers” for the killings of emergency responders.

U.N. humanitarian chief Tom Fletcher made the demands saying: “They were killed by Israeli forces while trying to save lives.”

After a ceasefire that lasted roughly two months, Israel relaunched its military campaign in Gaza on March 18. Since then, bombardment and new ground assaults that have killed more than 1,000 Palestinians, according to Gaza’s Health Ministry. The ministry’s count does not distinguish between militants and civilians, but it says over half those killed are women and children.

Mass grave

For days, Israeli forces would not allow access to the site where the emergency teams disappeared, the U.N. said.

On Wednesday, a U.N. convoy tried to reach the site but encountered Israeli troops opening fire on people.

The convoy saw a woman who had been shot lying in the road. The dashboard video shows staff talking about retrieving the woman. Then two people are seen walking across the road. Gunfire rings out and they flee. One stumbles, apparently wounded, before he is shot and falls onto his face to the ground.

On Sunday, the U.N. said teams were able to reach the site after the Israeli military informed it where it had buried the bodies, in a barren area on the edges of Tel al-Sultan. Footage released by the U.N shows workers from PRCS and Civil Defense, wearing masks and bright orange vests, digging through hills of dirt that appeared to have been piled up by Israeli bulldozers.

“Their bodies were gathered and buried in this mass grave,” said Jonathan Whittall, with the U.N. humanitarian office OCHA, speaking at the site in the video. “We’re digging them out in their uniforms, with their gloves on. They were here to save lives.”