Missoula police said the undercover detective involved in a Wednesday drug bust shooting is out of the hospital, and on administrative leave.
Police said the department automatically places any officer involved in a deadly force situation on paid leave.
They said officers may return to work only after an investigation determines the use of deadly force was lawful and justified.
Police said taking time off also allows officers to recover from any injuries, and to mentally process the incident, which may have been traumatic.
"You react as you were trained, and you are able to deal with the situation, but your brain isn't always caught up with everything, I mean you remember everything, but it could take a couple days for your full recollection to return," said Sgt. Jerry Odlin, of the Missoula Police Department.
If the undercover officer's identity was compromised during the Wednesday shooting, police said he can still return to work in the field, but likely on a new case.