I'm going to keep this really short and analysis free since I don't have any time to post much today--and I'm not an authority.
But I haven't seen any diaries on this yet.
During the dawn hours, after morning prayers, many people were killed (54 at current count, and over 400 wounded) at a protest at the Republican Guard headquarters.
The vast majority of those killed seem to be Morsi supporters, with at least one death and several injuries on the military/police side.
As one might expect, the pro-Morsi/Brotherhood protesters are calling this a massacre by the army...
and the army, as one might expect, claims that this was a response to terrorist activity by the Muslim Brotherhood. (over-->_
so far, there is video evidence that can be used to support either side's case, but no evidence of who started it.
Within Egypt, it seems that nearly all media outlets that might lean pro-MB have been shut down, so the narrative (widely supported by many Egyptians, it seems) is a pro-military one--i.e. that the MB 'started it' and that this was a necessary reaction by the military. I don't buy this (deliberate or not, this appears to be an enormous overreaction by the military)--but I am also skeptical of the fact that the MB rally was entirely peaceful.
No matter who 'started it', the fact that over 50 Morsi supporters have been shot and killed is horrific--and may point to the desire of certain elements on both sides to escalate the conflict (and blame the other side).
I'm withholding judgement--it's a bit like the 'coup/not-a-coup' debate.
Anyway, feel free to comment---excellent links in the guardian home page and by twitterers
and many others...