The bloodiest day in Gaza since the end of the 2014 war came as Donald Trump praised the embassy move as a "great day for Israel". Mr Trump's daughter, Ivanka Trump, will be among US officials attending the opening ceremony later today.
Palestinian health officials said a 14-year-old boy was among those killed in the first fatalities of what is expected to be a bloody day on the Gaza border. Hundreds more were reportedly injured.
The Palestinian Authority accused Israel of carrying out "a terrible massacre" and called for an immediate "an immediate international intervention" to stop the killing. Turkey said the US also bore responsibility for the bloodshed.
More than 70 Palestinians have been killed since protests marking the 70th anniversary of their displacement in 1948 began in late March.
Sixteen Palestinians were killed during protests in Gaza on Monday, hours before the new US embassy was due to officially open in Jerusalem, the Palestinian Ministry of Health announced.
The first victim to be named was Anas Hamdan Qdeih, a 21-year-old, who was shot dead east of Khan Younis, according to the Ministry, on a day of mass demonstrations along the Gaza border.
A Palestinian woman walks through black smoke from burning tires during a protest in Gaza on Monday.
The Ministry said more than 500 had suffered injuries
The Israeli army air-dropped leaflets over Gaza warning people not to approach the fence that separates Gaza from Israel.
More than 50 people have been shot and killed by Israeli soldiers since the latest wave of protests began in March, according to a CNN count based on the Palestinian Ministry of Health figures.
Demonstrators say they want to highlight their right to return to homes lost by their ancestors during the war that accompanied the founding of the state of Israel in 1948.
Israel says the demonstrations are orchestrated by Hamas, the militant group that runs Gaza.
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