Complex sentence: In November 1977, Israel initiated an exchange of fire that led to the death of several people from both sides of the border and finally Israeli bombing of the targets in South Lebanon during which 70 people, mainly Lebanese, were killed.
Split into simpler sentences: In November 1977, Israel initiated an attack that led to numerous deaths on both sides of the border. Israel also bombed the targets in South Lebanon during which 70 people, a vast majority being Lebanese, were killed.