Complex sentence: Days after the shooting, the IDF demolished the concrete cylinder and wall (along with bullet holes) that the al-Durrahs had sheltered behind, thereby destroying the crime scene; they said they did this to remove hiding places for snipers.
Split into simpler sentences: Days after the shooting, the IDF demolished the concrete drum and wall (along with bullet holes) that the al-Durrahs had sheltered behind, thereby destroying the crime scene. They said they did this to remove hiding places for snipers.