I've been living in Colombia for practically 6 years and have traveled almost all of this beautiful country, however not all of my experiences have been pleasant, I've had a lot of encounters with the paranormal (a whole lot), basically because I often get involved with people that are as curious as I am when it comes to exploring things unknown. The reason I'm sharing this experience is because it left me very shocked and frightened for a very long time (I usually tend to brush off most of my experiences). Anyway:
I'd been talking to a girl for quite a bit and we'd become good friends (let's call her Vanessa), we share a lot of similar interests including the paranormal and even got scared a few times during the night shifts at the hospital we're doing our internship in. The coordinator of the hospital gave a few interns a 3 day weekend (a lot for a medical intern), so Vanessa invited me to go and visit her village/town, which I gladly accepted. Her town (I won't say the name) is in La Guajira which is a "state" located in the north/north east of Colombia, it's a mixture of jungles and deserts, and it is notorious for being inhabited by large groups of Native Americans. The state is also known for its witchcraft, because of the Native American culture, and that it is not a very safe place to live in.
While being there I was introduced to a neighbor of hers who went by the nickname "El Indio", who was famous for doing cleansings, blessings, etc., like "good witchcraft". The second day there was when the event in question happened: I was hanging outside a store on the corner of the street drinking with Vanessa and talking to "El Indio" when this young man ran round the corner with tears in his eyes, he grabbed my shirt and begged for help, saying that some men were trying to kill him, he told us to please hide him somewhere. I was too shocked to even articulate a word; El Indio simply stood up his chair, sat the young man, took some kind of totem out of his pocket and started mumbling something I couldn't understand while casually resting his hand on the head of the man who came for help. I stood up and looked at Vanessa, but before I could say anything she just put her finger in her lips, telling me to shut up.
Less than a minute later two men armed WITH GUNS came by asking if we've seen this man, WHO WAS RIGHT IN FRONT OF THEM! Vanessa said she saw a guy walking by but didn't know if it was him. The two men looked at Vanessa, El Indio and me, and went on their way. They passed 2 more times in front of the store, in front of the man they were looking for, BUT NEVER NOTICING HIM. I just stood there, both shocked and amazed of what I was witnessing in front of me. The armed men eventually left. El Indio let go of the man and stopped his chanting, told the man to call his family to go pick him up, he thanked all of us for not telling the armed men and took off.
El Indio told me not to be afraid and eventually explained that the little "totem" in his pocket was something called "anima", which is some sort of nature spirit/demon/ghost that protects the owner through a pact or ritual that they make when the spirit in question is captured. He also asked me if I wanted to see him disappear. I said no because I was too shocked at the moment, although now I regret not seeing it. What I can't figure out to this day is how its possible for a human being to have that kind of power.
You can ask me anything you want (except personal information or the name of the town I was in); I'll try to answer all your questions.
Biblio: Yes, the gunmen looked at El Indio while asking for the man in question. Perhaps they didn't ask why he was mumbling to himself because they were carrying guns (Although little towns in Colombia can be dangerous, police can always be around the corner) and didn't want to be spotted. Your hypnotic chanting theory could really explain what was happening in the scenario, I never really pondered the possibility!
Tweed: The fact that the gunmen didn't recognize the person they were looking for is a real possibility, although they never really looked at the man that was sitting in the chair as if he didn't exist. The reason I was shocked to see this paranormal event happen despite the fact that I look for it on a daily basis is because it was the first time I saw something like this (Ghosts, demons, spirits are "normal" paranormal, people tend to talk about it so much and many have had experiences with it, however, someone dissapearing for another person is something I've never seen).