Israeli media said he had two young children. The third victim was lightly wounded.
In the Palestinian village of Kobar, in the central West Bank district of Ramallah, four Palestinians were detained by Israeli forces.
The Waqf, the religious authority that governs the site, published videos showing police firing tear gas at Palestinians inside the mosque compound.
The Israeli military did not comment directly on the deaths but said about 7,000 Palestinian "rioters" threw rocks and rolled burning tyres at soldiers, and at the fence itself, at several locations along the border.
Israeli forces detained at least eight Palestinians during predawn raids on Sunday across the occupied West Bank.
Israel rejects the widely held view that settlement expansion is one of the greatest obstacles to peace with the Palestinians.
Over 140, mostly unarmed, Palestinians have been killed since protests began.
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There was no response from Abbas's government, which has cut ties with the Trump administration over its stance on Israel.
"Such awful acts serve only those who stand in the way of peace".
Israeli raids into Palestinian towns and villages are near daily occurrence in the West Bank and East Jerusalem.
A Palestinian minor on Saturday succumbed to wounds he sustained from Israeli army fire near border of the Gaza Strip, according to a local medical source.
In a statement yeserday, the Ministry of Foreign Affairs said that because the Israeli occupation forces have not legally or morally deterred nor been under global pressure, they deliberately choose the holiest times and places in order to provoke the feelings of 1.5 billion Muslims in full view of the world.
Palestinian Islamist movement Hamas, which rules Gaza, has promised revenge after Israeli strikes on the coastal enclave killed a number of its members in recent weeks.
In a statement late Thursday, it praised the "courageous operation" in the Adam settlement without claiming responsibility for it.