 However, they lifted the siege on 30 March 598, at the approach of an Byzantine army led by Comentiolus, which had just crossed Mount Haemus and was marching along the Danube up to Zikidiba, only from Tomis.For unknown reasons, Priscus did not join Comentiolus when he pursued the Avars.Comentiolus made camp at Iatrus, however he was routed by the Avars, and his troops had to fight their way back over the Haemus.