Going to work this morning around 4:30am i turn on a access road to get on the Loop 289. As soon as i turn right i get a K band rear arrow. There is a LEO trailing way behind me and coming up fast. I drive fast to work because there is barely any traffic. The alert continues to get stronger C/O K band from the rear. I start slowing down to the PSL in the construction area ahead and he is on my tail before i know it and stays a 3-4 seconds on my bumper then decides to go around. With out the arrows i would have gun through the construction zone because there was a K band false coming up about a mile.