Many of the people treated for injuries following a rush on an aid convoy in Gaza on Thursday suffered bullet wounds, the UN has said.
UN observers visited Gaza City’s al-Shifa Hospital and saw some of the roughly 200 people still being treated.
Hamas has accused Israel of firing at civilians, but Israel said there was a “stampede” after its troops fired warning shots.
Leaders from around the world have called for a full investigation.
The incident unfolded after hundreds of people descended on an aid convoy as it moved along a coastal road, accompanied by the Israeli military, in the early hours of Thursday morning.
The World Food Programme has warned that a famine is imminent in northern Gaza, which has received very little aid in recent weeks, and where an estimated 300,000 people are living with little food or clean water.
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In footage from the scene, volleys of gunfire can be heard and people are seen scrambling over lorries and ducking behind the vehicles.
Gaza’s Hamas-run health ministry has said that at least 112 people were killed in the incident and another 760 were injured.
In a statement on social media, Rear Adm Daniel Hagari, spokesman for the Israel Defense Forces (IDF), said, “Dozens of Gazans were injured as a result of pushing and trampling.”
The IDF’s Lt Col Peter Lerner also told the UK’s Channel 4 News that a “mob stormed the convoy” and that Israeli troops “cautiously [tried] to disperse the mob with a few warning shots”.
Mark Regev, special adviser to the Israeli prime minister, had earlier told CNN that Israel had not been involved directly in any way and that the gunfire had come from “Palestinian armed groups”, though he did not provide evidence.
Giorgios Petropoulos, head of the Gaza sub-office of the UN Co-ordinator for Humanitarian Affairs (OCHA) told the BBC he and a team sent to al-Shifa hospital found a large number of people with bullet wounds.
He said all but a handful of the 70 to 80 patients in the emergency room he visited had been injured during the convoy incident.
In addition to those with bullet wounds, he said doctors had treated many who had fallen down or been trampled – but he was unable to say with certainty which group was larger.
Mr Petropoulos said those with bullet injuries had suffered wounds in the upper and lower body. One patient told him he had been shot in the chest and who had walked to Shifa to get treatment.
“He said they (Israeli troops) usually shoot in the air. This time, they shot into the thickest part of the crowd,” Mr Petropoulos said.
But, Mr Petropoulos emphasised UN personnel had not been present during the incident making it very difficult to know precisely what happened.
Dr Mohamed Salha, interim hospital manager at al-Awda hospital, previously told the BBC that they had received 176 of the injured, of whom 142 had bullet wounds.
