Clashes broke out between ISIS and Nusra Front militants on Lebanon's northeast border Monday following several days of relative calm, Hezbollah-affiliated media said. The War Media Center, which monitors fighting in the border Qalamoun area and other parts of Syria where Hezbollah is present, said the clashes broke out in Wadi al-Dibb, on the eastern outskirts of Lebanon's Arsal. At least one fighter was killed and another one wounded, the report added. The fighting is taking place southeast of Qalaat al-Hosn, it said. Nusra and ISIS had engaged in fierce clashes on Arsal's outskirts since late last month over a territorial dispute that left several militants dead from each group, but the fighting ended about one week ago following a truce. The Lebanese Army has also been striking the militants with artillery fire on the outskirts of Arsal and Ras Baalbek on a nearly daily basis for more than one year. Last week, the army carried out a major operation in Arsal which it said left six ISIS militants dead. Another 16 suspected ISIS fighters were arrested in the raids, one of whom is the prime suspect in last week's assassination of a police officer.