L.A. City Councilman Dennis Zine was not the only motorist who reported that Justin Bieber was flying down the freeway at breakneck speed ... TMZ has learned, a total of 10 drivers called 911.
We broke the story, Zine -- who was an LAPD motor cop for 18 years -- believes Bieber was traveling faster than 100 mph. Bieber's people dispute Zine's estimate, noting that the singer was cited for ONLY going 80.
But when Bieber was finally stopped by CHP officers, he was several miles from the point Zine spotted him, and Zine told us Friday night his100 mph estimate was "conservative."
And get this ... we're told someone from Bieber's security team was a passenger in his car and allowed Justin to put the pedal to the metal. Mind you, Justin was weaving in and out of traffic, baring squeezing in between moving vehicles.
As we reported, Bieber was being chased by paparazzi, but Zine maintains the 18-year-old jeopardized his life and the lives of others and he should have slowed down and pulled off the freeway.