Complex sentence: Law enforcement also stepped up its own campaign against the bandit--from the middle of 1948 until Giuliano's death Montelpre was occupied in some state of siege by law enforcement, making the inhabitants' lives miserable.
Split into simpler sentences: Law enforcement also stepped up its own campaign against the bandit. From the middle of 1948 until Giuliano's death Montelpre was occupied in some state of siege by law enforcement, making the inhabitants' lives miserable.