Following its success in Nambu a Ngongo, the Portuguese army advanced into Mbamba in November. The Portuguese forces scored a victory at the Battle of Mbumbi. There they faced a quickly gathered local force led by the new Duke of Mbamba, and reinforced by forces from Mpemba led by its marquis. Both the Duke of Mbamba and the Marquis of Mpemba were killed in the battle. According to Esikongo accounts, they were eaten by the Imbangala allies of the Portuguese. However, Pedro II, the newly crowned king of Kongo, brought the main army, including troops from Soyo, down into Mbamba and decisively defeated the Portuguese, driving them from the country at a battle waged somewhere near Mbanda Kasi in January 1623. Portuguese residents of Kongo, frightened by the consequences for their business of the invasion, wrote a hostile letter to Correia de Sousa, denouncing his invasion.