Israeli troops shot and wounded a Palestinian protester in Gaza on Friday as the final weekend of border demonstrations began.
Organisers said they expected tens of thousands of Gazans at border encampments in the coming days.
Israeli soldiers have killed 52 Palestinians since protests began on March 30 and more than 1,700 wounded by Israel army fire. No Israelis have been hurt, though protesters have thrown stones and rolled burning tyres towards soldiers along the border.
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Demonstrations end on May 15 - or Nakba Day - which marks the displacement of hundreds of thousands of Palestinians in the conflict surrounding the creation of Israel in 1948.
A senior Hamas official signalled support on Thursday for thousands of Palestinians to breach the border fence into Israel at protests to coincide with next week's US embassy move to Jerusalem.
Yahya Sinwar implied he would like to see thousands of Palestinians crossing into Israel in his first major briefing to international media since becoming Gaza head in 2017.
Asked what he wanted to see from protests on Monday and Tuesday, Mr Sinwar pointed out Israel has never specifically defined its borders.
"What's the problem with hundreds of thousands breaking through a fence that is not a border?"
Mr Sinwar said he hoped Israel would not shoot at what he called "peaceful" protests.
Israel has warned that it will prevent any border breach. It has stuck to its open-fire policies, such as targeting "main instigators" and those approaching the fence, despite growing international criticism. Israel has accused Hamas of using the protests as a cover for attacking the border.
Rights group say the use of potentially lethal force against unarmed protesters is unlawful.