The escalating conflict in Democratic Republic of Congo will dominate an African Union summit opening Saturday, with the DRC president absent after Rwandan-backed forces seized a second major city on his territory.

The Rwanda-backed M23 fighters claim to have taken control of Kavumu airport serving Bukavu, the capital of South Kivu province in the eastern Democratic Republic of the Congo (DRC). The airport, primarily used for NGO and military flights and where DRC troops had been stationed,

The absence of the president of the Democratic Republic of Congo at the recent meeting has raised concerns. WATCH: DRC conflict | Discussion | DRC senator comments on South Africa's role The escalating violence in the eastern region of the DRC as the country fights a proxy war with Rwanda must have played a significant role in this decision.