More complex bombs, such as the one that detonated on the corner of South Wadsworth Boulevard and Ken Caryl Avenue, had timers. The two largest bombs built were found in the school cafeteria and were made from small propane tanks. Only one of these bombs went off, only partially detonating. It was estimated that if any of the bombs placed in the cafeteria had detonated properly, the blast could have caused extensive structural damage to the school and would have resulted in hundreds of casualties.