A Pella man was killed in a car-versus-semi accident this morning on Highway 163 in Marion County.Sixty-two-year-old Terry Owens of Pella passed a semi on the stretch of highway. Once in front of the truck, though, officers say Owens tried to slow down or stop and was struck from behind by the semi. Owen’s vehicle rolled, and he was ejected. The driver of the semi, 32-year-old David Summers of Missouri, was not injured.