Big banks may have to contend with government’s legal reckoning, which has already cost them hundreds of billions of dollars, for years to come. (Mark Lennihan/AP)

JPMorgan Chase, the nation’s largest bank, said Wednesday it is being investigated by the civil and criminal divisions of the Justice Department over the sale of mortgage-backed securities in the lead-up to the financial crisis.

The investigation is the latest sign that federal prosecutors and regulators are not letting up in their efforts to hold Wall Street accountable for actions related to the crisis. It also means that big banks may have to contend with the legal reckoning, which has already cost them hundreds of billions of dollars, for years to come.

In a quarterly filing Wednesday, JPMorgan said the Justice Department’s Civil Division notified the company in May that it had preliminarily concluded that the firm broke federal laws in offerings of subprime and other nonconforming residential mortgage-backed securities from 2005 through 2007.

The company added that it had also received and responded to “a number of subpoenas and informal requests” from federal and state authorities concerning every aspect of the packaging and sale of mortgage securities.

There have been no formal charges filed against the bank, and the Justice Department and JPMorgan declined to comment on whether a lawsuit is in the making. Yet the investigation falls in line with cases the department has pursued as part of the Obama administration’s federal mortgage task force — a team of federal and state attorneys assembled in 2009 to go after crimes related to the financial crisis.

In January 2012, the task force launched a working group to investigate misconduct in the mortgage-backed securities market. Since then, the group has filed cases against Credit Suisse and JPMorgan for misleading investors about the quality of the securities they sold.

One of the group’s latest cases resulted in Justice filing charges Tuesday against Bank of America for allegedly hiding the risks associated with $850 million worth of securities backed by home loans. Justice claims the bank knew that more than 40 percent of the 1,191 mortgages it bundled into securities did not meet underwriting guidelines but sold them anyway.

Bank of America has bristled at the charges, defending the quality of the securities and insisting that investors had ample access to the underlying data on the loans.

In announcing the charges Tuesday, Attorney General Eric H. Holder Jr. said Justice will “continue to take an aggressive approach to combating financial fraud and uncovering abuses in the residential mortgage-backed securities market.”

He added that the task force will “use every tool, resource, and appropriate authority to ensure stability, accountability, and — above all — justice for those who have been victimized.”

Wall Street’s hand in the near-collapse of the economy has resulted in legal retribution with no end in sight. Some industry experts have criticized the lack of criminal prosecutions of high-ranking executives, but others say the series of multimillion-dollar settlements help prevent future wrongdoing.

“The language these banks understand is dollars,” said Mark Williams, a former bank examiner who teaches finance at Boston University. “The more they have to pay, the more pain they feel. And that may be the deterrent they need.”