Laden with just the possessions they can carry, thousands of displaced people have reached the outskirts of the city of Goma in eastern Democratic Republic of Congo, fleeing a rapid M23 rebel advance that has taken more territory than ever before.

NZULO, Congo -- The M23 rebel group's advance toward eastern Congo's largest city has displaced over 178,000 people in the past two weeks, the United Nations said, as the fighters closed in on Goma on the border with Rwanda.

U.N. Secretary-General Antonio Guterres has warned that Congo's M23 conflict risks spiralling into a broader regional war.