Keep in mind that newer versions of LOIC can be run idly in the background, connected to a control channel on IRC for remote activation by someone else. The amount of "coordination" necessary for a massive LOIC attack is limited to getting someone to download the software and enter the relevant channel information.

If memory serves, it's even easier than that: the version currently being distributed comes pointed at the CnC channel by default.

Yes, probably not this specific event, but maybe they were coordinated just in case something happen around the protest that went down yesterday.