The morning after burying 19-year-old Abdul Fattah Abdul Nabi, his family gathered in a tent set up to receive mourners, watching and rewatching a video of the moment they say Israeli soldiers shot him in the back of the head.
The video appears to show Abdul Fattah, dressed in black, running away from the border fence carrying a tyre. Just before reaching the crowd, he crumples under gunfire.
"He had no gun, no Molotov, a tyre. Does that harm the Israelis, a tyre?" asked his brother Mohamed Abdul Nabi, 22.
"He wasn't going towards the Israeli side. He was running away."
The teenager was one of at least 15 people killed by Israeli forces in the Gaza Strip on Saturday, during what Palestinian factions billed as a peaceful "March of Return" to mark Land Day, the anniversary of the expropriation of Arab-owned land by the Israeli Government in 1976. But it ended as the bloodiest day in the 362 sq km territory since the 2014 war between Israel and Hamas, the militant group that controls Gaza.
Israeli Prime Minister Benjamin Netanyahu praised the Israeli military for guarding the country's borders. "Israel will act firmly and decisively to protect its sovereignty and the security of its citizens," he said. The Israel military has warned that it will "expand" its response if violence continues. Hamas and other factions in Gaza have vowed to keep up demonstrations.
Abdul Fattah's family is among those demanding an investigation into the Israeli response to the protest, saying videos show he posed no threat. More than 700 people were injured with live ammunition in the demonstration, according to the Palestinian Health Ministry in Gaza. Another 49 were wounded, it said.
The UN called for a transparent, independent investigation. Israeli human rights group Adalah and the Gaza-based Al Mezan Centre for Human Rights wrote to Israeli Attorney-General Avichai Mandelblit to demand accountability. They said the use of such weapons against civilians was a "blatant violation of international laws." Israel said it stuck to strict rules of engagement to deal with a 30,000-strong crowd along the border, saying "rioters" threw Molotov cocktails and stones, burned tyres, and attempted to break through the fence.