WOBURN -- A personal banker from Wilmington was sentenced to three-to-five years in state prison on Monday safter she admitted to stealing more than $2.1 million from 31 investors and customers.

In Middlesex Superior Court on Monday, Elaina Patterson, 54, a former personal banker at Bank of America, pleaded guilty to charges of larceny over $250 from a person 60 or older (15 counts) and larceny over $250 (16 counts), according to the state Attorney General's Office.

In addition to the state prison sentence, Superior Court Judge Peter Lauriat placed Patterson on probation for 10 years after she finishes her sentence. While on probation, Patterson is prohibited from working in the financial services field.

A restitution hearing will be scheduled at a later date.

"This defendant's gross violation of trust negatively impacted more than 30 victims, many of whom were her friends and family, and others who were long-time and often elderly customers," Attorney General Martha Coakley said in a statement. "Through today's state prison sentence, she is being held accountable for her deceitful and illegal actions," she said.

During the scheme, the defendant conducted fraudulent transactions worth approximately $6 million and made payments back to investors and customers of nearly $3.8 million, leaving more than $2 million still owed.

Prosecutors say Patterson used $6 million she allegedly embezzled from 31 clients to buy expensive cars, luxury vacations, and make home improvements. She also paid for her children's private schools and college tuitions.

Patterson used the trust from friends and family and then pushed fake investment opportunities that promised high rates of interest, prosecutors said.

"Once this scheme began to unravel, we allege that she began to steal from customers in order to fund withdrawals from investors and cover her illegal activity," Coakley said in a statement.

She also funded her own lavish lifestyle, prosecutors allege. Patterson allegedly bought a variety of luxury cars -- a Cadillac Escalade, a Mercedes SUV, and a Lexus -- along with making extensive upgrades to her Wilmington home, according to prosecutors.

She also allegedly paid for expensive vacations to California, Aruba and Las Vegas, staying at hotels such as the Ritz-Carlton, the Hotel DelCoronado, the Bellagio and the Mirage, prosecutors allege.

More than $100,000 was allegedly used to pay for college and private-school tuition for her children, as well as paying for her children's apartments in California. She also allegedly made payments on multiple loans and credit cards.

Although she initially denied the thefts, Patterson eventually cooperated with the bank 's investigation and provided a written statement describing her conduct, according to court documents.

The attorney general's office began an investigation in November 2011 after the matter was referred by Bank of America during its initial internal investigation. Patterson worked as a personal banker at a bank branch in Reading, which was initially Bank of Boston, and later became Fleet Bank and then Bank of America

Authorities allege that between July 1999 and September 2011, Patterson made approximately $6 million in fraudulent transactions involving 31 investors and customers.

At the beginning of the scheme, Patterson allegedly persuaded family and friends to invest their money in accounts that she characterized as offering high interest rates, normally between 10 and 15 percent. Authorities allege that she regularly portrayed these accounts as being exclusively for high-level investors and corporations, but said that due to her position at the bank , she was able to set up these accounts for family and friends.

The investigation allegedly revealed that Patterson convinced 15 family members and friends to invest nearly $4.5 million as a part of this scheme, and that she issued fake certificate of deposit receipts and Form 1099s on bank forms to make the investments appear legitimate.

Authorities allege that, in a number of instances, Patterson set up accounts in the investors' names without their knowledge, put her own address on the accounts, deposited the investors' funds, and used the money both to fund payments to other investors and to funnel money into her personal accounts. 

Further investigation allegedly revealed that beginning in 2009, Patterson began stealing money from the accounts of customers, many of them elderly, to conceal her previous theft from investors.

Seven of the victims were 60 or older at the time they provided funds. The victims included Patterson ' cousins, some of her aunts and uncles, one cousin's wife's parents, her sister-in-law's parents and several people she met through her father-in-law.

To come up with the cash, the victims withdrew funds from legitimate savings and investment accounts, cashed in savings bonds and diverted funds that included tax refunds and lottery winnings. Two victims, with Patterson 's encouragement, took out six-figure mortgages on their homes to invest the money with Patterson .

Patterson allegedly stole almost $1.5 million from 16 different customers by forging signatures on withdrawal slips.

She allegedly used approximately $400,000 of this amount to repay customers stolen from earlier in the scheme and the majority of the balance of that stolen money to fund "interest payments" and other payments to the investors.

During an eight-year period between March 2002 and June 2010, Patterson transferred $1 million from a "shell account" for this scheme to her personal accounts.

When the investment money began to dwindle, by August 2009 Patterson began stealing from customers, especially older bank customers, prosecutors allege. Patterson allegedly stole from 16 customers, eight of whom were 60 or older and six were over 80.

The scheme unraveled in the fall of 2011, when a customer noticed that a CD had been closed without her knowledge or authorization. The customer came to the bank on Patterson 's day off and saw documents that listed showed the funds had been deposited in an account with the victim's name but with Patterson's home address.

Investigators uncovered about $6 million in alleged fraudulent transactions. Patterson made payments back to customers and investors of almost $3.8 million, leaving the total alleged net theft at more than $2.1 million.