Complex sentence: As the first police officer arrived at the scene and emerged from her vehicle, Yousef stabbed her in the neck just above her protective vest, her partner immediately drew his gun and shot Yousef four times, killing him.
Split into simpler sentences: As the first police officer arrived at the scene and emerged from her vehicle, Yousef attacked, stabbing her in the neck just above her protective vest. Her partner immediately drew his gun and shot him four times, killing him.