act
ajar
apprehend
arrested
bars
cage
cell
chain
closed
confined
convict
crime
criminal
delinquent
detain
discharge
door
empty
facility
freedom
grate
imprison
incarcerate
inside
iron
iron bars
jail
jail cell
justice
key
law
lawbreaker
lock
lock up
locked up
lockup
mechanism
metal
offender
offense
padlock
prison
reformatory
release
row
security
set free
unlock
villain