Discription of Events: Speeding and switching lanes less than car length in front of us. We moved to right lane they moved back in front of us and started hitting breaks. They went north to 71 at north market we went to hwy 1. They cut-thru back to hwy1 and followed us to Walmart parking lot and threw a sack with jar of Channelles tomato relish at and hit the front of our vehicle and sped away out of the parking lot.