Complex sentence: The operation, which was part of the 2010 Rio de Janeiro Security Crisis, was the State responding to drug traffickers setting buses and other vehicles on fire via combustible fuels, in various neighborhoods throughout the city of Rio de Janeiro.
Split into simpler sentences: The operation, which was part of the 2010 Rio de Janeiro Security Crisis, was the State responding to drug traffickers setting buses and other vehicles on fire using combustible fuels. These attacks occurred in various neighborhoods throughout the city of Rio de Janeiro.