A Palestinian woman has been shot dead by Israeli soldiers near the Gaza border fence, in another day of protests and violence, according to the Palestinian health ministry.

Razan al-Najjar, 21, was shot near Khan Yunis on Friday, bringing the toll of Gazans killed by Israeli fire since the end of March to 123.

According to health ministry spokesman Ashraf al-Qudra, Najjar was a volunteer with the ministry, wearing the white uniform of a medic when she was shot in the chest.

An Israeli army spokesman said they were looking into the report.

But the military said in a statement that “thousands of rioters” had gathered at five locations along the border, “burning tires adjacent to the security fence and attempting to damage security infrastructure”.

Shots were fired at an army vehicle and a Palestinian had crossed into Israel, planted a grenade and returned to Gaza, it said, stressing soldiers were acting “in accordance with the rules of engagement”.

An exchange of fire on Tuesday night started with a barrage of rockets and mortars into Israel from Gaza, prompting Israel to respond with strikes on 65 suspected militant sites in Gaza.

It was the worst flare-up since the 2014 war in Gaza and followed weeks of deadly demonstrations and clashes along the border, beginning on 30 March.

The protests have demanded that Palestinians who fled or were expelled in the 1948 war surrounding Israel’s creation be allowed to return to their former homes, now inside the Jewish state.

They peaked on 14 May when at least 61 Palestinians were killed in clashes as tens of thousands of Gazans protested the US transfer of its embassy in Israel to Jerusalem the same day.

Low-level demonstrations have continued since.