On 11 March 1978 , a PLO guerilla raid from Lebanon led to the Coastal Road massacre . Israel responded by launching an invasion of southern Lebanon to destroy the PLO bases south of the Litani River . Most PLO fighters withdrew , but Israel was able to secure southern Lebanon until a UN force and the Lebanese army could take over . The PLO soon resumed its policy of attacks against Israel . In the next few years , the PLO infiltrated the south and kept up a sporadic shelling across the border . Israel carried out numerous retaliatory attacks by air and on the ground
Coastal Road massacre
Coastal Road massacre
Israel