Israeli fire claimed the lives of eight children under the age of 16 on Monday during violent clashes on the Israel-Gaza border over the US embassy opening in Jerusalem, according to the Palestinian envoy to the UN.
"We condemn in the strongest terms these atrocities by the Israeli occupying forces, using this massive fire power against civilians who have the right to demonstrate peacefully -- and they have been demonstrating peacefully," said Ambassador Riyad Mansour.
The diplomat gave a toll of 45 Palestinian dead and more than 2,000 injured. The Gazan health ministry reported shortly afterwards that the number killed had risen to 52.
Mansour said Palestinians demand an immediate stop to the violence and, pointing to Israel, said "we want those responsible to be brought to justice."
The diplomat added that his colleague at the UN in Geneva was urging the UN Human Rights Council to hold an emergency meeting to launch an independent investigation into the clashes.
Mansour said the "massacre" was occurring as the US "illegally and unilateraly and in a provocative way is opening its embassy."
"It is very tragic that they are celebrating an illegal action while Israel is killing and injuring thousands of Palestinians civilians."
Monday's bloodshed make it the deadliest day of the Israeli-Palestinian conflict since a 2014 war.
Palestinian mourners gather around the body of a man who was killed during a protest at the Israel-Gaza border on May 14, 2018, during his funeral at a mosque in Khan Yunis in the southern Gaza Strip