Answer the flow of the public security traffic police department to investigate the scene when a traffic accident occurs: 1. If it is a traffic accident after on-site investigation, fill in the traffic accident registration form; 2, does not belong to the traffic accident, with the approval of the person in charge of the accident handling department, notify the parties in writing; 3. The scene of the accident investigation shall generally not be less than two people; 4. After receiving the report, the public security organ shall immediately send personnel to the scene to rescue the injured and property, investigate the scene and collect evidence. Legal Basis Article 72 After receiving the traffic accident alarm, the traffic administrative department of the public security organ shall immediately send traffic police to the scene, first organize the rescue of the injured, and take measures to restore traffic as soon as possible. The traffic police shall conduct an inquest and inspection on the scene of the traffic accident and collect evidence; Due to the need of collecting evidence, the accident vehicle may be detained, but it shall be properly kept for verification. The traffic administrative department of the public security organ shall entrust a specialized agency to conduct a professional inspection of the physical and mental condition of the parties. The appraisal conclusion shall be signed by the appraiser.