Largo police say they're searching for the person who drove off after hitting a woman and a child Thursday night in a Walmart parking lot. The hit-and-run happened at the Walmart on 2677 Roosevelt Boulevard, according to the police department. Based on preliminary information, investigators say a driver crashed into the woman and child, hit another car and then left the scene. The woman was seriously hurt while the child sustained critical injuries. They were both transported to the hospital. Police are searching for a silver Chevrolet Malibu with red rims and heavy front-end damage. The Walmart parking is shut down while police investigate. The public is asked to avoid the area.