Justin Bieber Car Chase -- L.A. City Councilman's 911 Call ... They're 'Driving Like Maniacs'

TMZ has obtained the urgent 911 call placed by L.A. City Councilman Dennis Zine -- moments after Justin Bieber blew past him on the 101 Freeway last Friday in his sports car ... allegedly breaking the 100mph barrier.

During the call, Zine tells the operator there's "a crazy chase going down" -- with 5 or 6 vehicles led by "a silver car" ... "cutting off cars" and "weaving in and out" of traffic at breakneck speeds.

Zine says they're "driving like maniacs."

Zine previously told us Bieber was going at least 100mph on the freeway -- but on the 911 tape, Zine says Bieber's going around 90.

You'll recall, Bieber was being chased by paparazzi as he flew down the freeway, weaving from lane to lane. Zine -- a former LAPD motor cop -- told us if he were on patrol he would have arrested the singer for reckless endangerment.

The CHP responded to Zine's call and a few miles down the Freeway Justin was stopped and cited for going 80.