The Agora Cyber Charter School missed Friday's deadline to turn over data on attendance, academic performance, and finances to the state Department of Education, as the department had demanded.

And what had been a departmental review of the cyber school has become an investigation into the operations of the online school, which has 8,500 students statewide.

"There has been concern regarding the accuracy of Agora's records and the timeliness of its reporting," Nicole Reigelman, a spokeswoman for the department, wrote in an email Friday. She said a team from the department had visited the school this week, but she declined to elaborate, saying the department does not comment on active investigations.

A series of letters obtained by the Inquirer show the department's growing impatience with Agora. Officials have been pressing the school for information about its operations since it laid off scores of employees in February without informing the state.

The department had directed Agora, which is based in King of Prussia, to submit complete, accurate data on testing and attendance by Friday or face "appropriate actions."

Officials have said Agora's problems recording student attendance raise concern about whether it is submitting inaccurate invoices to school districts and billing for students who are no longer enrolled.

Agora was also supposed to turn over detailed financial information, including monthly financial reports and copies of contracts negotiated after Jan. 1.

JoAnn Gigliotti, an Agora spokeswoman, had said on Tuesday that the school was working to deliver the data and financial records the department had requested.

Agora officials could not be reached for comment Friday on whether the school had complied or requested an extension.

The Education Department's efforts to obtain the information were mentioned only in passing during an emergency meeting of the Agora board Thursday evening.

"We met at length with [the department] today," said Jon Marsh, an independent consultant who has been hired to manage the school's day-to-day operations and serve as an adviser.

"Had a truly good exchange of information back and forth and were able to give them a lot of information they had been asking for," Marsh said. "And I think it was a lively exchange - lively in a good way. And I look forward to working with them as we move forward to next year."

The Education Department team was at Agora's headquarters from 10 a.m. to 3:30 p.m. Thursday, according to a source with knowledge of the matter.

Agora has been seeking a five-year renewal of its operating agreement from the Education Department since October 2014.

The department oversees Agora and the 12 other cyber charter schools, which provide online instruction to students in their homes.