CINCINNATI, Ohio – An Ohio charter school chain is under fire for importing a high percentage of teachers from Turkey, the home country of the company’s founders.

“An Enquirer investigation has found that Chicago-based Concept Schools, which runs Horizon and 17 other charter schools in Ohio, annually imports dozens of foreign teachers in numbers that far surpass any other school system in the state,” the news site reports.

“At least 474 foreign teachers, again mostly from Turkey, have arrived at Concept’s Ohio schools between 2005 and 2013. The schools are collecting about $45 million in state funds annually to educate 6,600 children in kindergarten through high school.”

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Concept Schools, which runs Horizon Science Academy in the Cincinnati suburb of Bond Hill, was founded by followers of a Turkish Islamic cleric, is currently under investigation from state and federal officials for possible issues with teacher licensing, testing and technology contracts, the news site reports.

Officials with the charter school chain contend they import teachers from Turkey to fill a shortage of math and science teachers, and because it’s the country they’re most familiar with.

Concepts vice president Salim Ucan told the Enquirer the international teachers also add to the cultural experience of students.

“These teachers are hired legally and are here legally,” Ucan said. “It’s not like we’re sneaking them across the borders. These are highly qualified people who have gone through the legal process to come here and make a difference in the lives of kids.”

Concept is one of several Ohio school districts that have imported teachers from Turkey and other countries in recent years, but the charter school chain is drawing fire because it recruits almost exclusively from Turkey, and at a much higher rate than other schools.

The teachers are coming to the U.S. with special H-1B visas, which allow them to work for three years, and to renew the visa for another three, before they must gain full citizenship. The H-1B visas were originally designed to allow companies to recruit highly skilled workers in fields like chemistry, biotechnology and engineering, the news site reports.

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Critics have complained that there are plenty of qualified teachers already in the U.S., but Concept is more focused on recruiting from its home country.

At least 80 Ohio school districts have employed teachers on H-1B visas, the Enquirer reports, but most only take in a few at most. Concept, on the other hand, currently employs 69 teachers on the special visas, or about 12 percent of its teaching staff, and nearly all came from Turkey or surrounding countries.

Ron Hira, an immigration policy expert and professor at the Rochester Institute of Technology, said “Concept may or may not be bending any rules, but the rules were written poorly in the first place.”

According to federal data obtained by Hira through a records request from the Immigration Department, “It seems clear from the data that these schools are favoring H-1B workers from a single source country, Turkey,” he said.

“American workers, as well as foreign workers from other countries, did not have a legitimate shot at getting these jobs.”

Concept Schools, however, are not the only school district under scrutiny for using H-1B visas. The Dallas school district is at the center of an ongoing criminal investigation into its use of H-1B teachers.

And in Prince George’s County in Maryland, the school district was fined $1.7 million and forced to repay more than $4 million in wages that were improperly withheld from foreign teachers, the Enquirer reports.