The Israeli military has provided new details that changed its initial account of the killing of 15 emergency workers near the southern Gaza city of Rafah last month, but said investigators were still examining the evidence.

The 15 paramedics and emergency responders were shot dead on March 23 and buried in a shallow grave where their bodies were found a week later by officials from the United Nations and the Palestinian Red Crescent. Another man is still missing.

The military initially said soldiers had opened fire on vehicles that approached their position "suspiciously" in the dark without lights or markings. It said they killed nine militants from Hamas and Islamic Jihad who were travelling in Palestinian Red Crescent vehicles.

But video recovered from the mobile phone of one of the dead men and published by the Palestinian Red Crescent showed emergency workers in their uniforms and clearly marked ambulances and fire trucks, with their lights on, being fired on by soldiers.

The only known survivor of the incident, Palestinian Red Crescent paramedic Munther Abed, also said he had seen soldiers opening fire on clearly marked emergency response vehicles.

An Israeli military official said late on Saturday the investigators were examining the video and conclusions were expected to be presented to army commanders on Sunday.

He said the initial report received from the field did not describe lights, but said investigators were looking at "operational information" and were trying to understand if this was due to an error by the person making the initial report.

"What we understand currently is the person who gives the initial account is mistaken. We're trying to understand why."

Israeli media briefed by the military reported that troops had identified at least six of the 15 dead as members of militant groups. However, the official declined to provide any evidence or detail on how the identifications were made, saying he did not want to share classified information.

"According to our information, there were terrorists there but this investigation is not over," he told reporters at the briefing late on Saturday.

The U.N. and Palestinian Red Crescent have demanded an independent inquiry.

The White House on Sunday said that President Donald Trump was holding Hamas responsible for the incident.

"Hamas uses ambulances and more broadly human shields for terrorism," said Brian Hughes, a spokesperson for the National Security Council. "President Trump understands the impossible situation this tactic creates for Israel and holds Hamas entirely responsible."

Red Crescent and U.N. officials have said 17 paramedics and emergency workers from the Red Crescent, the Civil Emergency service and the U.N. had been dispatched to respond to reports of injuries from Israeli air strikes.

Apart from the paramedic Abed, who was detained for several hours before being released, another worker is still missing.

The U.N. said last week that available information indicated one team was killed by Israeli forces, and other emergency and aid crews were killed one after another over several hours as they searched for their missing colleagues.

"We need justice for the victims and we need to ensure that all of those who are responsible are held to account," said Palestinian Red Crescent spokesperson Nebal Farsakh. "Without this, the crimes will continue to happen."

OPENED FIRE

The military official said initial findings from the investigation showed troops had opened fire on a vehicle at around 4 a.m., killing two members of the Hamas internal security forces, and taking another prisoner, who the official said had admitted under interrogation to being in Hamas.

As time passed, several vehicles passed along the road until, at around 6 a.m., the official said troops received word from aerial surveillance that a suspicious group of vehicles was approaching.

"They feel this is another incident like what happened at 4 a.m. and they opened fire," the official said.

He said aerial surveillance footage showed the troops were at some distance when they opened fire, and he denied reports that the troops handcuffed at least some of the paramedics and shot them at close range.

"It's not from close. They opened fire from afar," he said. "There's no mistreatment of the people there."

He said the soldiers had approached the group they had shot, identifying at least some of them as militants. He did not explain what evidence had prompted the assessment.

"And in their eyes they had an encounter with terrorists, that is a successful encounter with terrorists."

He said the troops had informed the U.N. of the incident on the same day and initially covered the bodies with camouflage netting until they could be recovered.

"There was no incident where the IDF tried to cover up. On the contrary, they called the UN immediately." There was no immediate comment from U.N. officials.

Later, when the U.N. did not immediately come to take the bodies, the soldiers covered them with sand to stop animals from getting at them, the official said.

He said the vehicles were pushed out of the way by a heavy engineering vehicle to clear the road, but he could not explain why the vehicles were crushed by the engineering vehicle and then buried.

The United Nations confirmed last week that it had been informed of the location of the bodies but that access to the area was denied by Israel for several days. It said the bodies had been buried alongside their crushed vehicles - clearly marked ambulances, a fire truck and a U.N. car.