New York Attorney General Eric Schneiderman on Monday filed a civil lawsuit against JPMorgan Chase and a pair of subsidiaries, alleging widespread fraud in the way that mortgages were packaged and sold to investors in the lead-up to the financial crisis.

The case was filed in New York State Supreme Court using the state’s Martin Act, which gives the attorney general broad powers to investigate securities-fraud cases. But it represents the first such case undertaken by the Obama administration’s federal mortgage task force, formed this year, of which Schneiderman is co-chair. It also marks the first in a string of similar actions likely to be filed by state and federal officials against other financial firms that dealt heavily in mortgage-backed securities.

The complaint filed by Schneiderman deals with conduct that took place during 2006 and 2007 at now-defunct Bear Stearns, the troubled Wall Street firm that was purchased in 2008 by JPMorgan Chase.

The case accuses Bear Stearns of deceiving investors about the shoddy quality of the loans that made up its mortgage securities. Schneiderman alleges that the firm failed to properly evaluate the loans, ignored problems that did surface and kept investors in the dark about its lack of due diligence and the questionable loans underlying the securities. The result, according to the suit, was far higher default rates among the loans than initially predicted, which translated into massive losses for investors.

The complaint also alleges that senior traders put “inordinate pressure” on underwriters to churn out mortgages by the hundreds each day, no matter the quality.

“The NYAG civil action relates to Bear Stearns, which we acquired over the course of a weekend at the behest of the U.S. government. This complaint is entirely about historic conduct by that entity,” JPMorgan Chase spokeswoman Jennifer Zuccarelli said in a statement, noting that the firm intends to contest the charges even as it fully complies with inquiries from investigators. “We’re disappointed that the NYAG decided to pursue its civil action without ever offering us an opportunity to rebut the claims and without developing a full record – instead relying on recycled claims already made by private plaintiffs.”

Schneiderman did not detail the amount of damages he is seeking. Rather, the suit requests that the firms be forced to relinquish any profits made as a result of the alleged fraud and pay restitution to investors who suffered because of it. The suit does not seek any direct damages for homeowners.

Schneiderman, who took office in January 2011, has long called for a more comprehensive investigation of the mortgage-related misdeeds that led to the financial crisis. Though he ultimately signed onto a $25 billion settlement this year between the government and big banks over shoddy foreclosure practices, he spent months criticizing state and federal negotiators as too willing in initial meetings to give banks a broad legal release for their practices. Those complaints caused acrimony and infighting among his peers, but it led the Obama administration to appoint him to the high-profile post on its mortgage task force.

A federal source familiar with the investigation said the Justice Department provided 12 investigative analysts to assist with Schneiderman’s investigations. In addition, the Federal Housing Finance Authority played a key role in the investigation, and numerous federal prosecutors interviewed witnesses and pored through reams of documents, the source said.

Government investigators have for years faced complaints about a lack of accountability for those in the financial world whose risky behaviors triggered the biggest economic collapse since the Great Depression. It remains unclear whether Monday’s lawsuit and others that are likely to follow will quell that criticism.

The Martin Act imposes a two-year statute of limitations on criminal misdemeanors and a five-year limit on felonies. The time limit for civil cases, however, is six years.

Monday’s filing pleased consumer advocates and liberal groups that have pushed for more-aggressive investigations into the causes of the housing bust.

“This filing is an encouraging first step to holding Wall Street banks accountable for the reckless and deceitful practices they have inflicted on homeowners,” Brian Kettenring of Campaign for a Fair Settlement said in a statement. “We hope that this case lays the groundwork for suing other big banks that left millions of American families foreclosed upon, jobless, or saddled with underwater mortgages.”

Schneiderman’s office and Justice Department spokeswoman Adora Andy declined to comment Monday evening.