Tornadoes swept through central Iowa Thursday afternoon.  They destroyed many buildings including the courthouse in Marshalltown and Vermeer Manufacturing in Pella as people were still working.  There are reports of several people with minor injuries. Meteorologists said the tornadoes formed suddenly and took everyone by surprise.  Other towns reported seeing funnel clouds including Prairie City, Colfax, Leighton and east of Des Moines past Altoona.