The extensive damage seen in a town southwest of Des Moines, Iowa, after a deadly storm on Tuesday, May 21, has indicated a tornado of “at least EF-3,” weather officials said on Wednesday.Drone footage captured by Tim Kastelein on Tuesday shows flattened houses and debris-covered streets left after the tornado ripped through the town of Greenfield.The National Weather Service (NWS) said on Wednesday that “additional damage evaluation will continue over the next several days and results are subject to change.”The tornado caused fatalities and injuries, according to the Iowa State Patrol. Credit: Tim Kastelein via Storyful