Topeka ? Gov. Mark Parkinson is seeking an outside review of Kansas’ prison system following allegations of widespread illegal sex between staff and inmates at the state’s prison for women.

Parkinson sent a letter Wednesday to the deputy director of the National Institute of Corrections in Washington, asking for the group’s help in finding an independent management expert to conduct a review.

This month, an area newspaper’s investigation showed that up to a third of the 250 employees at the Topeka Correctional Facility have been involved in an illegal black market that includes exchanging sex with female inmates for drugs.

Corrections Secretary Roger Werholtz has said only 2 percent of the department’s 3,000 employees have engaged in sexual misconduct.