Officials and residents say Rwanda-backed rebels have gained ground in eastern Congo despite the unilateral ceasefire they declared earlier this week, taking control of a town 100 kilometers (60 miles) from the provincial capital of Bukavu.

The march by Rwanda-backed rebels across eastern Congo risks escalating into a regional conflict, with countries such as Burundi, Uganda, and Tanzania already involved. Despite diplomatic efforts, tensions remain high.

Congolese troops have fought back against Rwanda-backed rebels who the U.N. says are moving fast into the South Kivu province after seizing the region’s largest city and an international airport