Female Palestinian medic Razan Al-Najar works at the scene of clashes at Israel-Gaza border, in the southern Gaza Strip. Picture: Reuters/Ibraheem Abu Mustafa

The Israeli army on Tuesday said its troops did not deliberately shoot a young Palestinian medical volunteer killed last week in violence on the Gaza border.

Razan al-Najjar, 21, was fatally shot in the chest on Friday near the southern Gaza town of Khan Yunis.

The Palestinian Medical Relief Society said she was hit "as she was attempting to provide first aid to an injured protester", adding that three other first responders were also hit by live fire on the same day.

An army statement in English said initial findings of its inquiry revealed "that a small number of bullets were fired during the incident, and that no shots were deliberately or directly aimed towards her."

It said investigations were continuing and conclusions would be passed to the Military Advocate General's department.

Gazans have since March 30 been holding border protests demanding the return of Palestinians to land they fled or were expelled from during the 1948 war surrounding Israel's creation, now inside the Jewish state.

READ: Israel vows to investigate after Palestinian medic shot dead in Gaza

The demonstrations are accompanied by smaller clashes as youths hurl stones at Israeli soldiers and attempt to breach the border fence, at times laying explosive devices on the fence or throwing grenades.

At least 125 Palestinians have been killed by Israeli gunfire on the border since March 30.

No Israelis have been killed.

The Jewish state accuses Gaza's Islamist rulers Hamas of organising the protests and using them as an excuse to carry out attacks.

Following Najjar's death, the UN envoy for the Middle East, Nickolay Mladenov, said in a tweet that "Medical workers are #NotATarget!" and that "Israel needs to calibrate its use of force and Hamas need to prevent incidents at the fence."