Guardian liveblog here.
Desperation play. This is going to seriously, seriously damage any attempts to rehabilitate the regime. It worked in Iran because of the theocratic pseudo-legitimacy of the regime and the patina of democracy that caused otherwise-reasonable people to presume that the (obviously rigged) 2009 election was legit. There's no such source of legitimacy in Egypt.
And, yes, these are obviously paid-off thugs and security forces.