oc·cu·pi·er

/ˈɑːkjəˌpajɚ/ noun, pl -ers [count]

1 : a soldier in an army that has taken control of a foreign place

— usually plural

The foreign occupiers were beginning to lose control of the area.

2 Brit : a person who is using or living in a particular building, apartment, room, etc. : ↑occupant

the current occupiers of the flat