Dyrl C. Buckner, 20, of Ocean Beach, has been arrested in connection with the death of a Pacific Beach man who was run over by his own van while trying to prevent its theft, San Diego police said. William Nothomb died Saturday at Scripps Memorial Hospital of injuries he suffered Jan. 15. Nothomb and his wife were awakened at 1 a.m. that night by what they thought was someone trying to steal their van. In their attempt to stop the theft, Nothomb was run over by the vehicle and fatally injured, and his wife was dragged several feet, police spokesman Rick Carlson said. Mrs. Nothomb did not require medical care. The van was found abandoned in Ocean Beach the following day. Buckner, described by police as a transient, was already in custody on unrelated charges when he was booked Monday on suspicion of murder, robbery and auto theft in the Nothomb case.