COLUMBUS (AP) — Ohio’s then-largest online charter school may have broken the law by withholding information used in calculating payments and inflated the amount of time students spent learning by not deducting the time they were inactive online, the state auditor said Thursday.

The Electronic Classroom of Tomorrow also didn’t document whether students were learning during times the company claimed for payment, according to the report from Republican Auditor David Yost.

“ECOT officials had the ability to provide honest, accurate information to the state and they chose not to,” Yost said. “By withholding information, ECOT misled state regulators at the Department of Education, and ECOT was paid based on that information.”

Yost said that could rise to a criminal act and he referred his findings to state and federal prosecutors for review.

A message left with an attorney representing ECOT wasn’t immediately returned. The school, which closed in January, has previously alleged the state engaged in a conspiracy to show the school had been overpaid.

The audit also said private affiliates should repay $250,000 in taxpayer money it used for television ads attacking a state effort to recoup funding due to overstated attendance figures.

The long-awaited review also incorporated input from a former ECOT technology employee who told The Associated Press that the now-shuttered e-school used software to intentionally inflate attendance figures tied to its state funding.

ECOT’s former spokesman has dismissed those allegations as mostly “made-up.”

Yost’s office had delayed the audit’s release as it obtained subpoenas for computer data from ECOT to preserve information should the dispute over $80 million in state overpayments be followed by a criminal case.

The Education Department previously found that the school significantly over-reported its number of full-time-equivalent students and owed the state $60 million for the 2015-2016 school year. Another $19 million penalty was assessed for 2016-2017.