Premise: July 28 (Reuters) - Seven Walmart stores in Missouri were evacuated after receiving bomb threats but no explosives were found, a Walmart spokesman said on Saturday. The threats were called in late on Friday to stores in Raytown, Gladstone, Jefferson City, Nixa, St. Peters and Ozark, spokesman Dan Fogleman said. The retailer is working with police to find those responsible, Fogleman said. No explosives were found and no injuries were reported.
Hypothesis: Raytown, Gladstone, Jefferson City, Nixa, St. Peters and Ozark, have a troublesome history with wasps.