A nun in western New York faces a criminal charge of grand larceny for allegedly stealing $128,000 from two rural parishes where she worked.

Sister Mary Anne Rapp pleaded not guilty in court Monday night to a second-degree grand larceny charge, according to NBC affiliate WHEC in Rochester, N.Y. Rapp, 67, is a nun with the Sisters of St. Francis and has been working at St. Mark's and St. Mary's Catholic Church in Holley, N.Y., WHEC reported. Holley is west of Rochester.

"She's been a nun for a very long time, been a very good person, never in any trouble before," said Rapp's attorney, James Harrington, according to The Associated Press. "She did great work wherever she was assigned."

Officials believe Rapp spent the money at casinos, and she reportedly had previously sought treatment for a gambling addiction.

"She spent 9 1/2 months in an in-patient treatment program and has maintained her recovery in the year since," said Sister Edith Wyss, provincial minister for the Sisters of St. Francis, according to the AP.

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Orleans County District Attorney Joseph Cardone in western New York said the embezzled money amounts to $128,000, WHEC reported.

A routine audit had found "some irregularities" and Rapp is accused of taking the money between 2006 and 2010, said a spokesman for the Roman Catholic Diocese of Buffalo, according to the AP.

The spokesman, Kevin Keenan, could not say how the alleged thefts had affected the day-to-day parish operations.

"These are smaller parishes in a rural part of the diocese," Keenan said, according to the AP. "Regardless of the size, this would be a significant amount of money for any parish."

The Associated Press contributed to this story.

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