Palestinian demonstrators have burned tyres and used tennis rackets to bat away tear gas canisters fired by Israeli troops as they fight a decade-old blockade of territory.
Israeli snipers and spotters were seen along the border, with live rounds being used to repel protesters.
Among those hurt in the clashes were seven who have been critically injured, including a 16-year-old boy who was shot in the face.
Speaking at the scene while tear gas canisters fell to the ground, Sky News Correspondent Alex Rossi said: “It is very volatile here. It is the seventh week of protests.
“So far today we’ve seen several people shot.
“Aid agencies say the humanitarian conditions have deteriorated in Gaza. We are expecting a very volatile few days here.”
He said that Israel has been accused of using excessive force, but it claims it is just protecting its border.
Rossi added: “It claims that Hamas is instigating – or at least has hijacked – these protests and is using them to camouflage acts of terror.”
The Gaza leader of the Hamas militant group has suggested tens of thousands of Palestinians could storm into Israel on Monday.
Yehiyeh Sinwar said the crowds will be unarmed, peaceful but “like a starving tiger” in pent-up anger and unpredictability.
Israel warned it would prevent any border breach, sticking to open-fire policies, including targeting “main instigators” and those approaching the fence.
It has accused Hamas of using the protests as a cover to attack the border, insisting it has a right to protect it.
Since the Hamas-led marches began at the end of March, 44 Palestinians have been killed and more than 1,700 wounded from Israeli army fire.
The protests are part of a campaign to break the blockade imposed by Israel and Egypt in 2007 after Hamas overran Gaza.
The border march on Monday will coincide with the historic movement of the US Embassy from Tel Aviv to Jerusalem.
Donald Trump’s decision to recognise Jerusalem as the capital outraged Palestinians, with the state’s leader describing it as “the slap of the century”.
On Tuesday, Palestinians will mark Nakba, referring to the mass uprooting during the Mideast war over the 1948 creation of Israel.
Hundreds of thousands of Palestinians were driven out of what is now Israel.