Investigations into two inmate suicides in Arizona prisons resulted in the firings of 13 corrections officers and sergeants and the disciplining of six other employees for failing to conduct security checks or other types of neglect of duty, the state Corrections Department announced Friday.

The investigations stemmed from a female inmate's 2015 death at a prison in Goodyear and a male inmate's February death at a prison in Florence, the department said.

According to the department, the investigations found numerous instances of neglect of duty and violations of the department's policies and ethics code.

In addition to failing to conduct security checks, those instances included dishonesty during investigations, falsification of records, failing to follow policy, failing to report or investigate misconduct by subordinates, leaving duty posts without authorization and failing to turn in keys and radios at the end of shifts, the department said.

"Our investigations uncovered troubling instances of neglect of duty and other serious misconduct by some employees which, as a public safety agency, we cannot and will not tolerate," Corrections Director Charles Ryan said in a statement.

The misconduct by the fired or disciplined workers doesn't represent the professional public service performed by the department's thousands of other employees, Ryan added.

The six employees disciplined included three correctional officers, two lieutenants and a deputy warden, and the discipline action range from letters of reprimand to suspensions without pay.

In addition, two additional employees received "corrective action with a letter of instruction," the department said.