* Oklahoma, Kansas, Nebraska and Iowa are hit by twisters * Some damage, but no widespread injuries reported so far (Adds tornado moved through Wichita, town hit in Iowa) By Kevin Murphy KANSAS CITY, Mo., April 14 (Reuters) - A spate of tornadoes tore through parts of Oklahoma, Kansas, Nebraska and Iowa on Saturday, churning through Wichita and other areas while causing property damage but no immediate reports of deaths or widespread injuries.