Nine South African soldiers have been killed in eastern Congo’s conflict zone, the South African defence department said on Saturday, as Congolese troops and peacekeepers battled to stop an advance by Rwanda-backed rebels on the city of Goma.

Democratic Republic of Congo and its allies earlier repelled an overnight advance on the provincial capital of over 1 million people, two army sources said. The sound of nearby heavy bombardment rocked the city in the early hours.