Unknown vandals desecrated an obelisk commemorating Asher and Yonatan Palmer, who were murdered near Kiryat Arba in September 2011.

The monument, erected near Hebron, was found Friday with the inscription bearing the victims’ names chipped off.

Police have opened an investigation into the incident.

Asher Palmer, aged 25, and his one-year-old son Yonatan died when two Palestinians pelted rocks at their car, causing Palmer to lose control of the vehicle, which overturned near the Israeli settlement of Kiryat Arba.

At first their death was thought to be accidental, but the police later concluded the car crash was the result of a terror attack. The perpetrators were caught and sentenced to jail terms.