Complex sentence: The picture is sent to Watts, who is seen looking at it while supervising the crime scene; at the scene, there is evidence of military-style tyre and boot tracks, and signs that DNA evidence may have been destroyed.
Split into simpler sentences: The picture is sent to Watts, who is seen looking at it while supervising the crime scene. Evidence is found of military-style tyre and boot tracks, and signs that DNA evidence may have been destroyed.