Justin Bieber was so out of control during his altercation with a neighbor Tuesday ... he had to be restrained by his bodyguard ... this according to the neighbor's account to cops.
We broke the story ... the neighbor claims Justin spit in his face and threatened to kill him after he complained that the singer was driving his Ferrari at around 100 mph in the gated community.
We've now learned ... the neighbor told L.A. County Sheriff's deputies ... Bieber wasn't done after hocking the loogie ... he was lunging at the 47-year-old man and the bodyguard had to restrain him. It's interesting ... because earlier this month a bodyguard had to restrain Bieber from attacking a rude photog in London.
Our Bieber sources say the singer insists he did not spit or attack the guy ... but as we reported, a landscaper directly across the street from Bieber's home says he saw the singer spit.