NEW YORK (CBSNewYork/AP) – The mayor says improving conditions on New York City’s troubled Rikers Island jail complex will require deep-seated cultural change.

Mayor Bill de Blasio said Thursday even he didn’t appreciate the extent of the problems until revelations of misconduct, violence and the maltreatment of the mentally ill emerged this year.

“Rikers Island has been a dehumanizing environment,” de Blasio said.

He called fundamental cultural change at Rikers one of his administration’s top priorities.

The mayor announced 90 percent of the jail’s top leadership has been replaced, WCBS 880’s Rich Lamb reported. He also outlined plans for reform including 7,800 new security cameras, cutting back on solitary confinement and the creation of a special unit with an unusual concentration of guards for highly-dangerous inmates who are responsible for the most of the violence.

While 2.2 percent of the jail’s population is the most violent, Commissioner Joseph Ponte said “67 percent of that group is involved in repeated incidents.”

“There’s no hesitation here on the question of how we change things and how deeply we can change things. We are convinced we can fix this problem,” de Blasio said.

De Blasio will take a tour of the jail on December 18, 1010 WINS’ Juliet Papa reported.

The Associated Press has reported extensively this year on the problems plaguing Rikers. The problems have included the gruesome deaths of two seriously mentally ill inmates.

About 40 percent of the roughly 11,000 inmates in the nation’s second-largest jail system have a mental health diagnosis.

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