He was behind me at a stop sign between Smith Street and Lasalle, and right as I ended my stop, he sped aggresively past me. While doing this there was contruction signs and material on the side of the road. I drove almost right after he passed the stop sign, and had to slam on brakes or swerve into him or contruction. He then contiued to speed going 40-50 in the 25 zones. I caught up with him at the long light on wilder and was able to capture his license plate. I also observed him on the phone while he continued to speed and I drove away.