Hebron is the largest Palestinian city in the West Bank, where some 200,000 Palestinians live along with 800 Jewish settlers protected by Israeli security forces.
Her funeral on Saturday began in her home town of Khuza'a.
"IDF troops responded by arriving at the scene and firing towards the suspects, who returned to the Gaza Strip", said the IDF.
She called it "grossly one-sided" for demanding a halt to what "excessive" Israeli force while not mentioning Hamas, the militant group that controls Gaza.
Israel's air force launched dozens of air strikes on targets in Gaza on May 29, 2018. Instead, it demanded that Hamas and other Palestinian militant groups stop "all violent activity and provocative actions" in Gaza.
The final draft called for "the consideration of measures to guarantee the safety and protection of the Palestinian civilian population in the Occupied Palestinian Territory, including in the Gaza Strip".
The Palestinian Medical Relief Society said Ms Najar had been trying to reach an injured protester when she was shot near the city of Khan Younis.
The Israeli military struck Hamas militant sites in Gaza early Sunday in response to the resumption of rocket fire toward Israel, which threatened to unravel an informal cease-fire that had held since a flare-up of violence last week.
At least four were fired from Gaza at Israel with three being intercepted and one fell short.
"Among the targets that were attacked were two sites used to manufacture and store weapons and a military compound", the Israeli army said.
Egypt also restricts movement in and out of Gaza on its border. The blockade, meant to weaken Hamas, has caused widespread economic hardship in Gaza.
"He did not pose any threat to them, he passed by them and could not hear their shouts and orders", Aref said, "Then, they just opened fire at him and his bulldozer, seriously wounded him, before removing him from his vehicle and left him to bleed on the ground". ( Yousef Basam/ TRTWorld ) Palestinians using sling shots fire stones along the illegally constructed fence in Gaza.
Footage circulating on social media showed Israeli soldiers pulling a man's body out of a small tractor standing in a street.
Izzat Shatat, 23, a volunteering ambulance worker, said he and Najjar were set to announce their engagement at the end of the holy month of Ramadan.
"She helped all people. She was the first to run toward anybody when he is shot", he said in tears.