Rwandan-backed rebels marched into east Congo's largest city Goma on Monday and Congolese troops exchanged fire with the Rwandan military across the border, in the worst escalation of a long-running conflict for more than a decade.

GOMA, Congo (AP) — Thousands fled the city of Goma on Monday as fighting raged between Congolese forces and rebels backed by neighboring Rwanda, who claimed to have captured eastern Congo’s largest regional hub.

The M23 militia, funded and directed by Rwanda, said it had seized the city of Goma, terrifying its people, many of whom sought shelter there after fleeing the rebel advance.