Threatened by ADT security personel

Yesterday 17 august 2015 around 18h15-18h20 (somewhere around that time or so), I was driving home along bram Fischer/Main road when the driver of an ADT vehicle reg number DS 70 KC GP, overtook me without warning and i had to brake to avoid ramming it him. When i hooted at him he didnt acknowledge his mistake then at the next stop , he got out of the car and came towards my vehicle in a threatening manner, luckily the traffic lights changed and he had to go back to his vehicle to drive off. At the next traffic lights , he got out again and approached me asking me to open my window which i refused to do as i wasnt sure of what he wanted to do. Fortunately again the traffic lights changed. this left me feeling very traumatized to say the least, and now i am scared of ADT and we use their services at my work place :(