Official accommodation for groups of spies? (5)
I believe the answer is:
cells
'groups of spies?' is the definition.
'cells' can be an answer for 'groups' (I have seen 'terrorist groups' mean 'cells' so perhaps 'groups' could also mean 'cells'). I am not sure about the 'of spies?' bit.
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for cells that I've seen before include "Basic structural units of all organisms" , "terrorist groups" , "Small rooms" , "Rooms for prisoners" , "Dungeons" .)