In a surprising move, Mike Bohn is out as the athletic director at the University of Colorado after eight years. Colorado administrators forced Bohn out, said a source with knowledge of the situation.

The Denver Post obtained an email Bohn sent to athletic department staff Tuesday afternoon which clearly indicated he was stunned by the news.

“This is a very disappointing, troubling and shocking development as we have made so much progress together over the past 8 years,” Bohn wrote in the email. “Regrettably, I am resigning as Athletic Director effective immediately. I believe it is best given the current circumstances. They want to go in a different direction and that is their prerogative.”

Colorado appointed former women’s basketball coach Ceal Barry as interim athletic director until a replacement is found.

Bohn indicated in the email he was not ousted for violating any provisions of his contract.

“I want to ensure you know…I have not engaged in any impropriety, NCAA rule violations, university policy violation or any immoral, dishonest, or other sort of misconduct.”

CU’s official stance is that Bohn resigned.

“I can tell you Mike has resigned as athletic director and that Chancellor (Phil) DiStefano has accepted his resignation,” school spokesman Branson Hilliard said in a phone interview.

Bohn’s resignation is effective June 3, the school said.

In a news release issued by the school, DiStefano said: “Mike Bohn led CU-Boulder athletics in a time of great transition and change. We are grateful to him for his vision, passion and commitment, and for his key role in revitalizing men’s and women’s basketball, helping us to join the Pac-12 Conference, and in taking important steps to upgrade athletic facilities at CU-Boulder. We wish him well.”

In a statement from CU president Bruce Benson, he said: “I support Chancellor Phil DiStefano’s decision to accept Mike Bohn’s resignation and seek new leadership for athletics at CU-Boulder. I appreciate Mike’s commitment to CU-Boulder over the past eight years. The athletics department is positioned to take steps to move the program to the next level, and I am confident we will find a leader who will be a key part of the team that will get us there.”

DiStefano said the search committee to replace Bohn will be looking for a “talented leader who can build on Mike’s vision and make it a reality.”

CU’s new athletic director will be asked to supervise a huge fundraising campaign. In February, the university announced a $50 million facilities fundraising campaign as the anchor of a $170 million multiyear upgrade of CU athletics facilities at Folsom Field and the Dal Ward Center, as well as the development of an indoor practice facility.

Bohn, who grew up in Boulder and graduated from Boulder High in 1979, was named the CU athletic director in April 2005 after working as AD at San Diego State for 18 months.

In August 2011, Bohn received a five-year extension from the Board of Regents and the Chancellor that secured him into 2017.

In addition to moving Colorado from the Big 12 to the Pac-12 in June 2010, Bohn has overseen the hiring of 11 head coaches: Mike MacIntyre, Jon Embree and Dan Hawkins (football); Tad Boyle and Jeff Bzdelik (men’s basketball); Linda Lappe and Kathy McConnell-Miller (women’s basketball); Roy Edwards (men’s golf); Liz Kritza (volleyball); Danny Sanchez (women’s soccer); and Ann Elliott (women’s lacrosse).

Before San Diego State, Bohn was athletic director at Idaho for five years (1999-2003). During his career, Bohn has worked on the athletic department staffs at the Air Force Academy (1984-92) as well as Colorado State (1996-98). He also worked for the College Football Association.

Bohn left Boulder out of high school and played baseball at the University of Kansas, graduating in 1983.

Anthony Cotton: 303-954-1292, acotton@denverpost.com or twitter.com/anthonycottondp

David Krause: 303-954-1893, dkrause@denverpost.com or twitter.com/dkrausedp