An Alpharetta charter school has spent taxpayer money to hire workers from overseas, run international field trips without proper supervision and give business to a related non-profit, an audit released Tuesday shows.

The audit, ordered by Fulton County Public Schools, questions management and financial decisions by leaders of the academically acclaimed Fulton Science Academy Middle School, one of about 130 charter schools with ties to Turkish imam and educational leader M. Fetullah Gulen.

They include a decision to secure a $19 million loan and break ground on a new building for the middle school and companion elementary and high schools, before knowing if the middle school’s charter would be extended.

The academy’s request for a 10-year charter extension was turned down by the Fulton school board last winter and the state in May, largely due to financial and management issues. The academy refused a county offer of a shorter term contract and plans to continue as a private school.

The findings raise questions about the oversight of charter schools, which use tax money but are given far more autonomy and flexibilty than regular public schools, said Fulton schools superintendent Robert Avossa, who released the audit at a school board meeting.

“How did this happen?” Fulton school board member Gail Dean asked during Tuesday’s discussion.

Officials of the school didn’t respond to the audit Tuesday.

Avossa said a charter school’s governance board has chief responsibility for oversight of operations, though, in this case, the audit offers evidence that members of the middle school’s board had conflicts of interest.

“That’s why the conflict of interest is such an issue. That’s the rub,” Avossa said. He said the middle school received $3.7 million in tax dollars last year and more than $30 million over its 10 years of operation.

Additional audits are planned at the nearby charter Fulton Sunshine Academy elementary school and Fulton Science Academy High School, which have overlapping management staffs, the superintendent said. They still have charter status. Together the three schools have about 1,250 students.

Avossa said he will await the response of administrators at the middle school before deciding whether to forward the audit to federal officials or prosecutors.

Middle school officials received a copy of the audit early Tuesday. One member of the school’s governing board, Ayhan Korucu, said he expects school leaders to issue a statement Wednesday. Calls to other board members, the principal and a public relations representative weren’t returned.

Concerns about the school’s financial and management practices have been raised previously, including by State School Superintendent John Barge when the charter extension was denied. The construction loan, Barge said, threatens the financial viability of the three charter schools.

Fulton hired a forensic auditor in February, in part to determine what taxpayer money or assets belonged to the school system, Avossa said. Auditors from IAG Forensics said that when they went to the school to examine records they were met by an “environment of resistance and obstructionism.”

The audit shows that Fulton Science Academy spent nearly $75,000 helping new employees -- and in some cases, their relatives -- who were coming from overseas to maneuver through the immigration process.

Even with Georgia public school systems shedding employees and other well-educated people seeking work, the school hired about 20 percent of staff from foreign countries, mainly Turkey. Most were hired to teach electives and one was hired as human resources manager, the audit found.

Auditors also reported finding “numerous inter-relations between the school, its vendors and other interested parties.”

In one case, the academy paid $239,366 to non-profit Grace Institute for Educational Research and Resources Inc. of Alpharetta, whose board included at least three employees of Fulton Science Academy Middle School, including the school’s then-executive director, Selim Ozdemir; principal, Kenen Sener; and curriculum director, Ali Ozer.

Grace Institute had the same address as the school at least one year, the audit found. It also found that Grace had only two paid staffers -- a receptionist and an IT person -- neither of whom had experience in the services Grace was hired for.

The academy also hired Atlantic Wind Productions for video production services, advertising and other services in December 2010, six months after the company was created and five months after its president, Baybars Bakay, ended a seven-month stint as a teacher at the middle school.

Asked about Bakay’s relation to the academy, school officials told auditors Bakay had been a computer science teacher at the school “maybe five years ago,” the auditors said.

The audit also discusses field trips to Turkey in 2011 and 2012. Almost half of the 33 people who participated in a summer 2011 trip did not appear to pay their own airfare, the auditors found. They said they found no evidence that background checks were performed on adults who traveled with the students and teachers and noted that, on one of the trips, some chaperones did not return with the group and stayed in Turkey longer, possibly on vacation.

“It is unknown where the trip participants stayed, where they ate while they were traveling, and how these expenses were paid for,” the auditors wrote.

Elizabeth Hooper, a public school parent from north Fulton, said the audit findings point to problems that can come from giving charter schools autonomy.

“Why would anyone think it is a good idea to remove oversight of how taxpayer money is spent?” she asked. “Taxpayers need to know who is spending their money and where. And the legislators who want to remove that from public view are obviously doing it for reasons that have nothing to do with public education.”

Fulton County is considered charter-friendly, with 9,000 of its 93,000 students attending 12 local charter schools.

Charter schools are a small but powerful force in the national education reform movement. State legislative leaders are among their biggest supporters and in the last legislative session pushed through a constitutional amendment that, if approved by voters in November, will reinstate the state’s authority to approve charter schools over local school district objections.

Gulen-influenced schools, which emphasize math and science, have grown rapidly into one of the nation’s larger collections of charters. That has brought scrutiny of their associations with Turkey.

Lou Erste, director of the state Department of Education’s charter school division, said one or two charter schools around the country typically will run into major financial problems every year. In Georgia, he said, “I’ve not seen anything quite like this.”

The fact that Fulton Science Academy Middle School had to apply for renewal of its charter application helped shine the light on the school’s problems, Erste said.

“This points to the fact that the law works,” he said. “They failed on every part of the test but academics.”

-- Russell Grantham and John Perry contributed to this article