Violence flared up again today in the troubled southern region when several bombs went off in the centre of the capital. Support for the rebels is growing, and it's expected that the rebels will succeed in bringing down a government that is increasingly unpopular. There are fears that a full-scale civil war may break out.
Is it natural to use the indefinite article in this passage? If so, what would be the rule to back it up?
We've got a clear picture of the region and the capital where the unrest is taking place. We know who the rebels are, and what they stand for (since support for them is picking up). Why a government then?