A Catholic nun has been arrested for allegedly embezzling more than $850,000 from Iona College in New Rochelle, N.Y.

According to a statement from the U.S. Attorney’s Office in Manhattan, Mary Thornton stole the huge sum of money from 1999 to 2009 while she was the school’s vice president of finance.

Thornton submitted false invoices and had the college pay her personal credit card bills during that 10 year period.

Thornton pleaded not guilty and was released from jail. Thornton’s attorney Sanford Talkin said she expected to reach a resolution that all sides can agree on.

In a statement, Iona officials said they were aware of the theft more than a year ago and terminated Tornton at that point.

“We took immediate action to terminate the employee and independent forensic auditors were retained to investigate thoroughly the allegations of financial fraud, waste and abuse,” the college said. “As a result of that in-depth investigation, new procedures were implemented to prevent a recurrence of the situation and the College complied with all regulatory reporting requirements.”

The Sisters of St. Joseph, Thornton’s religious order, said Thornton had been recalled and had her activities restricted. The order also said Thornton had been told to cooperate with investigators and that she was being given emotional and spiritual support.

There was originally a discrepancy in the amount Thornton allegedly embezzled. The U.S. attorney originally said it was more than $1.2 million before revising that figure to $850,000 at the suggestion of Iona.  

“Unfortunately, the US Attorney’s Office used the overstated number in its initial release of information to the news media before correcting it two days later,” the college said in a statement.

Iona says it has replaced Thornton, recovered most of the money and have moved on from the theft.

“Today, we have a new CFO and staff in place; we have recovered the majority of the missing funds; and, from the College’s perspective, the matter is considered closed,” according to the statement.

The school is located 15 miles from Manhattan and has about 4,200 students.

– The Associated Press contributed to this report.