The additional scrutiny comes after a previous audit found 29 guns were missing. That audit was conducted after an October shootout with a suspect led to the discovery of two stolen guns in his vehicle. The number of missing firearms turned out to be much higher.
The unaccounted firearms include 29 fully automatic weapons, 20 short-barrel shotguns and one short-barrel rifle, according to KPHO.
"It is unacceptable for any law enforcement agency to be this negligent to not keep accurate records and to allow for weapons to be distributed in a manner that doesn't have any oversight or accountability," Sheriff Paul Penzone said.
Penzone blamed the previous administration of former Sheriff Joe Arpaio and said no weapons have gone missing since he took over the department.
"At the end of the day, we're going to get them all back," Penzone said.