After three years on the run from the Rwandan-backed M23 insurgency in eastern Congo, on Sunday, with the rebels fighting their way into Goma's city outskirts, Colleta Nzambonimpa found herself in church with nowhere left to turn.

The militia seized the pivotal city of Goma, threatening a new humanitarian crisis in a region that has suffered decades of fighting.

Congo has severed diplomatic ties with Rwanda as fighting between Rwanda-backed rebels and government forces rages around the key eastern city of Goma.