Michigan State Police are investigating a crash on I-94 Wednesday that closed the highway for a few hours. It happened shortly after 1 p.m. on eastbound I-94 near M-140 in Watervliet. Troopers say a Berrien County Sheriff’s Department patrol car was escorting a slower moving semi off the road when a pick-up driven by a 32-year-old Hartford man crashed into the back of the patrol car. That caused the patrol car to crash into the semi in front of it, and then into another semi to the side. The sergeant in the patrol car was taken by ambulance to Lakeland Hospital and the driver of the pick-up was taken to a hospital in Kalamazoo. The crash caused traffic on eastbound 94 in the area to be rerouted on to I-196. The road was back open around 4 p.m.