On June 3, 1996, at 1805 central daylight time, a McDonnell Douglas MD-82, N493AA, registered to and operated by American Airlines as a scheduled Title 14 CFR Part 121 flight, encountered severe turbulence 35 NM north of Childress, Texas. Two flight attendants and seven passengers sustained minor injuries and three crew members and 56 passengers were not injured. Instrument meteorological conditions prevailed and an instrument flight plan was filed. American Airlines Flight 722 originated from El Paso, Texas, and was en route to Chicago, Illinois. The aircraft was approximately 30 miles north of Childress, Texas, at FL330 when it encountered severe turbulence for approximately 5 seconds. Fort Worth Center had issued Flight 722 a left/right deviation clearance for weather, which was about 80 miles ahead, and the aircraft was on this deviation when the turbulence was encountered. The First Officer was flying the aircraft in IMC, and no cells were being painted on the aircraft's radar in the immediate area. The nearest cell being painted was approximately 20 miles right of track. Convective sigmets 99C, 01C, and 02C were in effect for New Mexico, Texas, Oklahoma, and Kansas. The flight attendants were providing service to the passengers, the seat belt light was illuminated, and all passengers were seated when the severe turbulence was encountered. The flight crew advised ATC and diverted to Oklahoma City, Oklahoma. The two flight attendants and seven passengers were taken to a local hospital, and were treated and released. An inspection of the aircraft revealed no damage, and it was released for flight.