By Tony Romeo

HARRISBURG, Pa. (CBS) — The Pennsylvania Board of Probation and Parole says three employees have been fired as the result of an investigation following last summer’s murder of an off-duty Philadelphia police officer.

The alleged killer had been released from prison just ten days before the murder (see related story).

Police say Rafael Jones shot and killed veteran officer Moses Walker Jr. last August, during a pre-dawn robbery attempt (see related stories).

Now, the Board of Probation and Parole has announced the findings of its investigation of the circumstances surrounding Jones’ release on “special probation.”  Spokeswoman Sherry Tate says three employees have been terminated.

“What I can tell you is that they were terminated due to violations of board procedures, the board’s code of conduct, and shortcomings in the manner in which Jones was supervised,” Tate said today.

But she declined to provide any other details, including what positions the terminated employees held.

Tate does say that the board is making changes as a result of the investigation, which will include pursuing the use of GPS tracking to replace the current electronic monitoring system.