The parties agreed on a truce late on Thursday under the mediation of the Lebanese parliament speaker, Nabih Berri.
As the clashes between the two groups erupted again, the sounds of fired rockets had been heard in the nearby city of Sidon and its neighborhoods, the National News Agency (NNA) reported late on Friday.
Fatah and Ansar Allah first engaged in clashes in mid-October. The situation escalated earlier this week when an explosive device blasted near a Fatah checkpoint, prompting the Lebanese military to deploy additional troops at the site to maintain order there.
Two Lebanese soldiers had been injured in the violence in Mieh w Mieh on Thursday. Moreover, media reports suggested that a Fatah member had been killed in the hostilities.