"At that time, M23 did not have many soldiers, so when the fighting was hard, they were calling us for help. Then we would come over the border and take the town," he said. "When we finished, we would pull back to Rwanda and allow M23 to occupy the area." Three times, his unit went over the frontier and into battle at M23's request, helping to seize the border crossing at Bunagana and two other towns. In September, however, Nsengiyumva's unit was deployed to bolster an M23 assault on a big Congolese army camp. This battle was tougher than expected – two attacks were beaten off and Rwandan forces with their rebel allies only succeeded at their third attempt.