Complex sentence: A large, intense tornado caused severe damage in the towns of Atoka and Tushka where many houses were destroyed or flattened from what was at times a double tornado with two well-defined vortices.
Split into simpler sentences: A large, intense tornado later caused severe damage in the towns of Atoka and Tushka. In both towns, many houses were destroyed or flattened from what was at times a double tornado with two well-defined vortices.