By mid-December, wild rumors started to fly about an upcoming communist insurrection that was to take place in the extreme north provinces against the government of President Juan Esteban Montero.
In the cities of Vallenar and Copiapó the rumours were that the insurrectionists were going to take over the Esmeralda regiment barracks and the police headquarters on Christmas night, as the first step to a full-fledged revolution.
The lieutenant and soldiers at the guard caught by surprise had to retreat to the infirmary where they were able to mount a hasty defense.
When the news reached the superior authorities, a decision was made to nip the revolution in the bud.
On the other side, three policemen and two soldiers died, plus an unarmed civilian who happened to be passing by and was hit by a stray bullet.