CHICAGO (CBS)–A south suburban bank employee accused of transferring $328,000 from the bank accounts of elderly customers was sentenced on Monday to four years in prison.

Christine Lange, 48, of Summit, Illinois, entered a guilty plea in July to a felony theft charge. Judge Robert Miller handed down her prison sentence Monday.

(DuPage County State’s Attorney)

While employed as an account executive at the Trust Company of Illinois (TCI) Bank in in Downers Grove, Lange allegedly made 84 transfers from the bank accounts of three customers, sending the money to her personal bank account, the state’s attorney’s office said.

The thefts occurred between September 2012 and June 2016, according to the state’s attorney’s office. All of the victims were in their 90’s.

TCI Bank refunded the customers, and Lange was ordered to pay the money back to the bank, the state’s attorney’s office said.

“The crimes Christina Lange committed against three elderly women are despicable,” said Cook County State’s Attorney Robert Berlin in a press release. “Her simple greed caused unimaginable hardship to her victims who relied on that money for their retirement and everyday living expenses. Unfortunately, the elderly can at times be seen as an easy target when it comes to financial crimes.”

Authorities started investigating after one of the victims noticed missing money and contacted police.

Lange was arrested in July 2017 and served 10 days in jail until she posted bond, the state’s attorney’s office said.

She is required to serve half of her sentence before she is eligible for parole.