CONCORD, Calif. (KGO) -- Concord police are looking for a gunman who shot a driver on Highway 242 Saturday afternoon. The driver is recovering in the hospital.Traffic was backed up for hours.Police say 911 calls came in about a person in a silver SUV opening fire on another SUV. They arrived within minutes of those calls and shut down Highway 242 just after 3:45 p.m.Drivers were diverted off the freeway as police combed over the asphalt looking for clues that may help track down the shooter.Police say the victim was able to drive himself to John Muir Hospital in Concord."The victim was struck a couple of times to his upper body. There are a number of holes on the left side of this vehicle," Concord PD Cpl. Christopher Blakely said.Officers talked with him briefly before he went into emergency surgery. He was only able to give minimal information about what happened.So far, only a couple other witnesses described a white SUV opening fire on the victim's gold Mercedes Benz SUV.Police are hoping to connect with more witnesses."The freeway at that time was probably packed with cars. And there's probably multiple witnesses who saw what happened but didn't want to call or report it. We strongly encourage any of those witnesses who saw what happened to call our dispatch center. Because we'd absolutely love to talk with them," Blakely said.Highway 242 was shut down for a couple of hours as police conducted their investigation. It was reopened just before 6:30 p.m.Police don't have a motive and they don't know if this is somehow connected to other freeway shootings that have happened recently in the East Bay.