Complex sentence: Many people ran into the O.J. Williams dry goods store, however, the store was swept away, and the people taking shelter in the basement were pelted to death by flying bricks and timbers.
Split into simpler sentences: Many people ran into the O.J. Williams dry goods store, which turned out to be a death trap. The store was swept away, and the people taking shelter in the basement were pelted to death by flying bricks and timbers.