I am reporting a potential unintended automatic emergency braking event involving a 2025 Tesla Cybertruck. On 23Mar2026, at approximately 40 mph, I was traveling behind a Tesla Cybertruck on a public roadway. There were no visible obstacles, hazards, or debris in the roadway that I observed. The Cybertruck suddenly and aggressively braked without warning. The abrupt deceleration appeared inconsistent with road conditions and is consistent with what is commonly described as âphantom braking.â As a result of the sudden stop, I was unable to avoid a collision with the rear of the vehicle despite maintaining a reasonable following distance. After the impact, the Cybertruck initially left the scene, stating they were unaware a collision had occurred. No debris or roadway hazard was documented at the scene in the police report (FVPD report #2026-00777). The other driver later indicated a plastic bag may have triggered the vehicleâs emergency braking system. I am submitting this report as a potential safety issue involving unintended or inappropriate automatic emergency braking behavior.