According to police reports, at 9:11am a caller reported he was traveling westbound on 4th Street and Galvin Ave when he was rear-ended by another vehicle traveling southbound on N Galvin Avenue.
The impact from the second vehicle, which police now know was driven by stabbing suspect Brandon Noll, caused the first vehicle to complete a 360-degree spin. Noll fled on foot after the crash, stole another vehicle, and was involved in a high speech chase before being apprehended. The full timeline of events is available here.