Palestinians in Rafah have been expressing their grief and outrage after protesters marching against Israel's raids on a neighbouring refugee camp were hit by Israeli fire.
Rafah's small hospital was quickly overwhelmed
People covered in blood fled the scene after several large explosions went off among a crowd of several thousand.
"What happened today is a massacre - Apache helicopters firing missiles at a demonstration and tanks firing shells," Dr Ali Moussa told the BBC, after receiving dozens of casualties at Rafah's ill-equipped hospital.
The army said that there were gunmen among the marchers and that soldiers fired a series of shots, including tank shells, to warn them off but had not deliberately targeted the protesters.
"All the casualties we received in hospital, all of them were injured by rockets," Dr Moussa said.
"We are doctors and we examined all these casualties - everyone is gashed with many injuries in the head and the chest and we extracted many pieces shrapnel from their bodies during the operations."
Doctors were overwhelmed by the scale of the suffering, with many casualties being treated in blood-soaked stairwells and corridor
Relatives came to identify bodies inside in a makeshift mortuary - made out of a flower cooler donated by a local flower shop - due to lack of space in the hospital.
Outside the hospital, people crowded around for news of relatives and friends who had been at the march.
"Did you see my brothers, the three of them who were in the rally?" cried one person, while others shouted out names in the hope of receiving news.
Some local residents described how explosions had gone off in their midst.
"I was at the front and dropped immediately to the ground. My friend was hit in the leg," said 15-year-old Samir Salam.
Another said the march had nothing to do with paramilitary groups - contradicting Israeli assertions that troops had fired warning shots when they saw armed men.
"There were no armed people at all - our point was to get the Israelis to open up Tel Sultan because people there need food, medicine and to feel more secure," said Abu Hashem.
Dr Moussa said most of the victims of the blasts were under 18 years old.
"Until now there are 20 casualties, most of them children, in critical condition," he told the BBC.
Failing to cope
Israeli troops went into Tel Sultan, a part of Rafah refugee camp, on Tuesday to attack militants and destroy smugglers' tunnels that they say are used to bring weapons from across the border with Egypt.
They sealed off the camp and place it under a curfew. At least 24 Tel Sultan residents have been killed by Israeli fire, including militants and civilians.
Most of the dead were school-age children
The death toll in Wednesday's missile strike and shelling has added at least 10 people to the figures.
Dr Moussa said medics had tried to transfer serious cases to larger hospitals by ambulance but the roads are difficult to pass. He alleged that on occasions the Israeli army opened fire at emergency vehicles.
"For three days we cannot transfer patients by ambulance on the main road or even the side roads," he said.
"We cannot manage - in any country in the world even a big hospital could not manage this task," he said.