Rescue workers clear the scene of a pileup on U.S. 23 at Willis Road near Ann Arbor, Mich. Severe morning fog Wednesday triggered three separate pileups involving a total of 60 vehicles that injured about 30 people on the highway south of Ann Arbor, authorities said. No fatalities were reported in the crashes, but Sgt. James Westrick of the Washtenaw County Sheriff's Department said 12 of the injured were reported in unstable condition. "According to investigators it was caused in part by severe fog, speed and driver error," he said.