Unidentified men allegedly attacked Palestinian farmers and Israeli activists harvesting olives outside the West Bank settlement of Yitzhar, near Nablus, on Sunday, injuring four.

According to the Rabbis for Human Rights NGO, whose activists were at the scene assisting the Palestinian farmers, several settlers descended the slope toward the group harvesting olives and attacked them with metal bars and stones.

A 71-year-old and an 18-year-old volunteer were said to have been injured, as were two Palestinians, identified by the Palestinian Ma’an News Agency as Nemr Issa al-Tirawi, 29, and his brother Qusai, 27.

The attack came a day after settlers near Nablus reportedly destroyed 100 Palestinian-owned olive trees in the latest attack of its kind, Al Jazeera reported.

The head of Rabbis for Human Rights claimed the IDF was not doing enough to protect the Palestinian farmers from settler violence.

“We’ve hear a lot of promises from the security forces in recent months about protecting the Palestinian harvest and farmers’ olive trees,” Rabbi Arik Asherman said in a statement. “In a lot of cases we also saw real intent. But it’s surprising to us that masked men succeeded in descending not a short distance from Yitzhar to attack, when the IDF knew that the olive harvest was going on there today, that the area is notorious for violence, and that farmers and our volunteers were attacked in the same place last week.”

An IDF spokesman told The Times of Israel that the army was unaware of the incident in question.

In 2012, the United Nations Office for Coordination of Humanitarian Affairs reported 98 incidents of settler violence resulting in 150 Palestinian injuries, and 268 incidents of attacks damaging Palestinian property.