Two US-backed groups in Syria are in open war against each other: “A Dier Ezzor Military Council (DEMC) leader announced his militia was in a guerrilla war against the Syrian Democratic Forces (SDF). Ethnic tensions between Washington’s Arab and Kurdish partners in Eastern Syria boiled over last week, with analysts warning fighting could escalate. So far, at least 100 people have been killed in the fighting taking place near American soldiers.”