“This is a cycle in Congo. It’s been almost 30 years this has been happening again and again and again. And (it) is devastating to see the same civilian populations are moving again and again.”

Goma – the largest city in the east of the Democratic Republic of Congo - has an official population of 2 million people. But more than half a million displaced people are now also living there, following a spike in fighting between the Congolese army and the Tutsi-led M23 rebel group around the town of Sake - just over 20 kilometres away.

Sake is on the main road that connects Goma to the rest of the region – meaning the city is all but cut off for supplies by road.

Aid agencies say if the rebel group were to move into Goma it would be an even greater disaster for the local population.

But how likely is that, and what is M23’s goal?

Presenter: Alan Kasujja @kasujja.