Complex sentence: Notes found by investigators after the incident, indicate that the primary motivation for such bulldozer rampage was his fight to stop a concrete plant from being built near his shop; these notes indicated that he held grudges over the zoning approval.
Split into simpler sentences: Notes found by investigators after the incident indicate that the primary motivation for the bulldozer rampage was his fight to stop a concrete plant from being built near his shop. These notes indicated that he held grudges over the zoning approval.