STILLWATER, Okla. — A woman suspected of driving under the influence plowed into a crowd Saturday during the Oklahoma State University homecoming parade, killing four people — including a toddler — and injuring dozens more in a collision that sent some spectators flying through the air.Stillwater police Capt. Kyle Gibbs said the woman's Hyundai Elantra struck an unoccupied motorcycle of an officer who was working security at the parade, then went into the crowd.