The Massachusetts attorney general's office is investigating Santander bank's auto lending business over concerns that the company may be engaged in the type of predatory practices that, on a larger scale, led to the mortgage and financial crises.

The office is looking at whether Santander lent to borrowers who were unlikely to repay the money and sold those loans to Wall Street, where they were packaged into securities and resold to investors.

Attorney General Martha Coakley subpoenaed Santander's U.S. auto finance company to produce documents related to borrowers' credit histories, the interest rates they were charged, and how the loan risks were described to investors, Coakley spokesman said Brad Puffer told The Boston Globe.

"We are using our experience, gained in holding banks responsible for unfair and predatory mortgage loans, to ensure consumers are protected in other areas of lending," Puffer said.

Santander said in a statement it is cooperating with investigators and its policy is "to comply with all lending and loan servicing laws as well as the rules and guidance of our supervisors and regulators."

The lending pattern at issue is one that many mortgage lenders followed in the run-up to the housing bust, which ultimately resulted in widespread loan defaults, worthless securities and the near collapse of the banking system.

Because auto loans are only a fraction of mortgage debt and it's far easier to repossess a car to recover money than to foreclose on a home, the practices aren't likely to have similar consequences.

Santander became a dominant player in the subprime market in 2006, when it paid $636 million to buy Drive Financial Services, a Dallas lender specializing in subprime loans. Drive was renamed Santander Consumer USA, and its business has grown as it bought other auto lenders and built relationships with nearly 14,000 dealerships.