The United Nations is expressing deep concern at reports of M23 rebels and Rwandan troops advancing south towards the DRC city of Bukavu on Thursday. The rebels, who have already captured the largest city in the country’s eastern region of Goma, say they want to take their fight to the far-off capital, Kinshasa. DRC President Felix Tshisekedi is calling for a massive military mobilization against the rebels. VOA’s Esther Githui-Ewart spoke to Gavin Declan, the managing director of Exigent Risk Advisory in Nairobi, Kenya, for an analysis into the latest escalation of violence.