Renowned philanthropist and author Greg Mortenson has been accused of spending charity money on personal expenses, including gifts, vacations and charter flights. An investigative report released Thursday claims that Mortenson mismanaged his ostensibly nonprofit organization, and a settlement arranged with the state of Montana requires him to pay more than $1 million in restitution to his own charity.

Mortenson is the co-founder of the Central Asia Institute, which aims to empower communities in Pakistan and Afghanistan through education. He also wrote two New York Times bestselling books: Three Cups of Tea, with a coauthor, and Stones Into Schools on his own. Both books promote the idea of achieving peace through education.

The books' claims have also come under scrutiny. Last year, author Jon Krakauer alleged that both books contained fabrications, and the story was reported on 60 Minutes.

Thursday's report focused only on Mortenson's charity, pointing to unaccounted-for funds and an overall lack of transparency, reports the Asscociated Press. Credit cards under the charity name were used by employees and family members to pay for items like gifts and club dues. In general, donations far exceeded charitable spending.

The report does not call for the dissolution of the Central Asia Institute, which is still more than solvent with $23 million saved. Instead, more oversight is suggested.

Mortenson's pursuits are noble and his achievements are important. However, serious internal problems in the management of CAI surfaced. Despite the severity of their errors, CAI is worth saving, said Montana Attorney General Steve Bullock.

Mortensen lost his position as the Central Asia Institute's executive director last year, in the wake of controversies surrounding his books. He still works as an employee of the organization, and the new director told AP that he is still important to the charity and will continue to play a role.

Mortenson cannot afford to pay his $1.05 million fine immediately, but has already remitted nearly half and has three years to pay the rest.