By Joe Parkin Daniels, Vice News
When Nicolás was 17 he was forced to kill eight of his friends.
"It hurt to kill them, obviously," Nicolás said, bowing his head as his voice started to tremble. "But an order is an order. I couldn't think about that."
Nicolás had been with Colombia's largest rebel group, the Revolutionary Armed Forces of Colombia, or FARC, since he was 12. Some of his condemned brothers in arms were as young as 14. Their crimes included trying to desert, and falling asleep during lookout. One had ruined the camp's food. Burning rice is an executable offence in the jungle. Refusing to carry out the executions would have got Nicolás killed himself.
Nicolás is able to tell the tale because, a year later in April 2015, he deserted himself.