MALDEN — State officials voted Monday night to permit a Chicopee charter school to establish a second location in Westfield, over the objections of critics who claim the school has ties to a controversial US-based Turkish cleric accused of planning a failed coup in Turkey last summer.

The claims, brought to the state by attorneys for the Turkish government under President Recep Tayyip Erdogan late Friday afternoon, just one business day before the vote, awkwardly thrust the Board of Elementary and Secondary Education into a contentious international dispute.

Critics of the Hampden Charter School of Science claim that the school is part of “a loose affiliation’’ of 160 to 170 US charter schools in 25 to 30 states founded by Turks loyal to cleric Fethullah Gulen. The cleric has denied any connection to the coup attempt, but had said it is possible some of his followers could have been involved.

Mitchell D. Chester, the commissioner of Elementary and Secondary Education, said the charter school has a track record of success, and its critics had not proved their claims.

“I’ve found no evidence to support these allegations, either relating to the existing charter school or to the proposed charter school,’’ he said.

Even if school leaders and teachers did have ties to Gulen, Chester said, that would not disqualify them from operating a charter school. The state education department does not ask charter applicants to discuss their political or religious views, he said.

John C. Martin, an attorney for the London-based international law firm Amsterdam & Partners, claimed “Gulenist schools’’ abuse a type of visa intended for foreign workers with specialized skills to bring in teachers from Turkey — thus denying jobs to qualified American teachers — and then overpay the Turkish teachers and force them to pay kickbacks to Gulen’s followers.

Volkan Yesilurt, chairman of the school’s board of trustees, denied the allegations and insisted, “our school does not have any kind of affiliation with any social, religious, or political movements. . . . Our curriculum is not affected by any movement or any ideology.’’

Members of the education board commented on the extraordinary nature of the claims, which member Ed Doherty likened to a John Grisham legal thriller and chairman Paul Sagan called “one of the most unusual situations I certainly have seen in a couple of years here.’’

Referring to the 11th-hour filing of the objections to the new charter, member Katherine Craven said, “This is like being thrust into an international mystery that happened at 5 o’clock on Friday, basically.’’

After more than two hours of testimony and discussion, the board voted, 5-3, in favor of giving a charter to the Hampden Charter School of Science-West, with Doherty, Margaret McKenna, and Mary Ann Stewart voting no, and Craven abstaining.

The panel also approved charters for Old Sturbridge Academy Charter Public School, a K-8 school to be located in Sturbridge, by a vote of 5-4, and for Map Academy Charter School, a high school to be located in Plymouth, by a vote of 8-1.

After the vote, Tarkan Topcuoglu, Hampden Charter School’s director, said he was relieved that the board had looked past the allegations.

“We’re not interested in any political issues or international issues they’re trying to bring to our table,’’ Topcuoglu said. “What we really care about is the students.’’

Material from the Associated Press was used in this report. Jeremy C. Fox can be reached at jeremy.fox@globe.com. Follow him on Twitter @jeremycfox.