A woman who kept the books for the Mission Houses Museum confessed to stealing $50,000 from her employer and is facing felony charges in state court, said Vickie Kapp, deputy city prosecutor.

An Oahu grand jury returned an indictment Tuesday charging Judy Vierra with first-degree theft and use of a computer to commit the theft.

Kapp said Vierra made 33 unauthorized transactions from Aug. 31, 2008 to Mar. 31, 2010 paying herself overtime and salary increases. When police confronted her about the transactions, Vierra confessed, Kapp said.

In a written statement, the museum said it has implemented increased oversight and financial controls since discovering the theft last year.

"We remain committed to ensuring that each donor dollar is put toward the preservation and interpretation of this important site in Hawaiian history," the statement said.