Palestinian roadwork destroyed portions of a 3,200-year-old wall on the biblical site of Joshua's altar on Mount Ebal, near Nablus, the right-wing NGO Shomrim al Hanetzach reported on Wednesday.
The area is located in Area B of the West Bank, which is under the civilian control of the Palestinian Authority.
Shomrim al Hanetzach said that Palestinian workers had ground ancient stone from the site's exterior wall into gravel to pave the road as well as made use of stones from within the site itself.
The altar remains intact, but could face future damage, the NGO said.
