Scattered reports throughout the day on Friday mentioned Yemeni security forces using live ammunition on protesters in 'Aden. Worse news has now emerged from San‘a: According to a Human Rights Watch report, a gathering of about a thousand peaceful demonstrators in San‘a's Tahrir Square was attacked by "hundreds of men armed with knives, sticks, and assault rifles" as they chanted slogans in celebration of the Egyptian revolution and against the Saleh regime.

Human Rights Watch witnessed at least 10 army trucks carrying men in civilian clothing to Sanaa's Tahrir Square, where a crowd of around 1,000 Yemenis had been demonstrating in support of the historic changes in Egypt and against the Yemeni government. Hundreds of men, their arrival coordinated by uniformed security agents, attacked the anti-government protesters with knives and sticks, prompting the majority to flee.

The full report is here. I should note that while HRW calls the demonstrators "anti-government protesters," I really have no idea just what these people were demonstrating for. The point is, Saleh's forces have used excessive violence against civilians in the capital. I was confident, a week ago, that something like this was possible, but given everything that's happened since then, I really thought Saleh had chosen another path. This was not only brutal and appalling, but politically stupid.

The JMP, which was likely not behind this particular gathering, will have no choice but to respond to this, in their own self-serving way, while non-mainstream protest groups will probably react as well. As always, we hope that their reactions are peaceful, but I'm not going to pull an Obama and ask the kid throwing a rock at a tank to "show restraint." Twenty-four hours ago I was feeling very critical of those tweeters who rushed to say that Yemen is next in line for revolution. But honestly, if Saleh doesn't know better than to pull crap like this, there is no telling what could happen in the next week or month.