1) Barred from leaving 2) Behind bars 3) Composer died behind bars 4) Confined 5) Cooped up 6) Fenced in 7) Housed like Tweety 8) Imprisoned 9) In a zoo 10) In an aviary 11) In captivity 12) In prison 13) In the zoo 14) Incarcerated 15) Kept behind bars 16) Like a gnu in a zoo 17) Like a zoo animal 1) Imprisoned 2) Pent 
• (a.) Confined in, or as in, a cage; like a cage or prison. • (imp. & p. p.) of Cage
Caged (kājd) adjective Confined in, or as in, a cage; like a cage or prison. 'The caged cloister.' Shak. 
Referring to the practice of placing high-value or sensitive products in a fenced off area within a warehouse.