Rescue workers walk through a neighborhood destroyed by a tornado Monday, May 23, 2011, in Joplin , Mo. A massive tornado that tore a six-mile path across southwestern Missouri killed at least 89 people as it smashed the city of Joplin, ripping into a hospital, crushing cars like soda cans and leaving behind only splintered tree trunks where entire neighborhoods once stood. (AP Photo/Jeff Roberson)