Complex sentence: Now all of the other cartel leaders knew what would happen if they were extradited, and soon after, the Medellín cartel organizations split up, and a violent war began as the cartel leaders tried to protect themselves by fighting back.
Split into simpler sentences: Now all of the other cartel leaders knew what would happen if they were extradited, and soon afterward, the Medellín Cartel organizations split up. A violent war began as the Cartel leaders tried to protect themselves by fighting back.