GOMA, Congo — M23 rebels seized the town of Minova in eastern Congo, a key supply route for the provincial capital Goma, authorities said Tuesday, leading to a mass exodus of people in the face of a new offensive by the rebel group, which has taken several strategic towns in recent weeks.

The provincial governor of South Kivu, Jean-Jacques Purusi, confirmed the capture of Minova, adding that the rebels have also captured the mining towns of Lumbishi, Numbi and Shanje in the same province and the town of Bweremana in neighboring North Kivu province.

Congo’s military said in a statement Tuesday that the rebels made “breakthroughs” in Minova and Bweremana. It did not confirm if M23 captured the towns.

M23, or the March 23 Movement, is a militant group composed of ethnic Tutsis who broke away from the Congolese army just over a decade ago. The group rose to prominence in 2012 when its fighters seized Goma, the capital of North Kivu province and eastern Congo’s largest city, on the border with Rwanda.

M23 is one of about 100 armed groups that have been vying for a foothold in mineral-rich eastern Congo, in a decades-long conflict that has created one of the world’s largest humanitarian crises. More than 7 million people have been displaced.

Congo, the United States and U.N. experts accuse neighboring Rwanda of backing M23. Rwanda denies the claim.

M23 has been making significant advances in eastern Congo in recent weeks. The rebels captured the key mining town of Masisi in North Kivu earlier this month, another key supply route for Goma.

Minova is a strategically important port on the shores of Lake Kivu and a transit point for many agricultural goods heading to Goma, about 28 miles away.

More than 237,000 people have been displaced by the fighting in eastern Congo since the beginning of this year, the United Nations refugee agency said in a report Monday.