abstract
amnesty
background
barb
barbed
black
border
boundary
cable
captivity
civil
close
closeup
conflict
construction
crime
danger
dangerous
enclose
escape
fence
flare
forbidden
freedom
guard
isolated
law
legal
metal
military
order
prison
private
prohibited
protect
protection
remote
rights
safety
security
shape
sharp
steel
symbol
system
texture
violence
war
warning
wire