It was the worst single-day tragedy in Ukraine since the revolution began in February, when former President Viktor Yanukovych was overthrown and more than a hundred people died in Kiev.

As is the rule today, social media played a part in bringing the events in Odessa to light. At least two web videos live streamed the initial clashes between pro-Russian and pro-Ukrainian activists and then showed fighting at the trade union building. Twitter provided photos, updates, and commentary. Facebook was inundated with postings.

From the safety of my living room in Kiev, I watched it unfold: the first people killed by gunfire, the pitched battles in the center of Odessa, and the retreat by the pro-Russian forces to the trade