Traffic collision at North Mountain Avenue Heard on: San Bernardino County CA Fire Dispatch 00:05 Traffic collision, medic engine twelve, North Mountain Avenue and West Twenty-third Street. Transcript This transcript is auto-generated from live dispatch audio and may be incomplete or inaccurate. It is not an official report and may change. Traffic collision, medic engine twelve, North Mountain Avenue and West Twenty-third Street. 2026-10-29 15:07 UTC Traffic W 23rd St & N Mountain Ave, Upland, CA 91784 View on map