Reply #119: The term has been in use for at least many decades

[pinboy3niner]

I remember it being used a lot during the Cold War. Here's one definition:

Noun 1. minder - someone (usually in totalitarian countries) who is assigned to watch over foreign visitors; "I turned around and there, a few hundred feet away, was our government minder, Li Wong Su, huffing and puffing toward us"

http://www.thefreedictionary.com/minder

Referring to Libya, the term is used particularly to describe the government officials without whom foreign journalists are not permitted to travel.