AUBURN — The Lake Auburn Watershed Protection Commission got a surprise this summer when its treasurer eyeballed its banking statements and saw something amiss.

Somebody with no authority snatched $100,000 or more with an unauthorized electronic transfer, commissioners said Friday, potentially leaving the government agency in the lurch.

Rick LaChapelle, vice chairman of the panel, said quick action by Treasurer Tracy Roy made it possible for the agency to retrieve most of the money.

Even so, the thief made off with $29,000, according to Angelynne Amores, director of marketing and communications for the City of Lewiston.

Amores said that Roy had notified the FBI about the theft. Who stole the cash remains unclear.

Chapelle said the loss to the agency could have been much worse had Roy, who is also Lewiston’s finance director, not been “right on top of it.”

He said the commission doesn’t have a lot of transactions so it could have been a while before anyone noticed the problem. But Roy saw it quickly, he said, and immediately notified the bank. Amores said Roy closed the account.

LaChapelle said the agency and the unidentified bank are hashing out whether the financial institution should cover the lost money from the unauthorized transfer.

“It’s frustrating,” he said.

Amores said Key Bank initially told the commission that no funds had been removed from its account, but it later changed its stance and informed the agency it could not recover about $29,000.

She said the agency is waiting to hear from Key Bank, with which it is negotiating. The commission has also turned in the case to an insurance company, Amore said.

With an annual budget of $212,000, the commission’s role is to protect the water quality of Lake Auburn, which provides drinking water for Lewiston and Auburn. It has commissioners from Lewiston, Auburn, Turner, and Buckfield.