Another Art Theft

I'm beginning to think stealing art is a national sport in South America. The latest picture to be stolen is Francisco de Goya's engraving Tristes Presentimientos de lo que ha de suceder (1810-1815) which Google translates as "Tristes presentation of what has happened". The engraving - from Goya's series Disasters of War - was stolen from the Gilberto Alzate Avendano Foundation in Bogota, Colombia, last Thursday night. Question: Why did the thieves select this engraving out of the 80 on display? Next question: Is there any sign of a break-in?