(Reuters) — New York's top law enforcement official said he plans to help bring more fraud cases against the world's biggest banks for selling shoddy mortgage-backed securities before the 2008 financial crisis.

Eric Schneiderman, the state's attorney general, said some of these banks were involved in the same kind of wrongdoing that has led him since 2012 to join the federal government in multibillion-dollar cases against JPMorgan Chase & Co., Bank of America Corp. and Citigroup Inc., the three-largest U.S. banks.

"Obviously there were many more institutions involved," Mr. Schneiderman said in an interview this week. "So there will be more cases."

Mr. Schneiderman co-chairs a working group on mortgage-backed securities that President Barack Obama created in 2012 to ensure accountability for the financial crisis.

The attorney general said that group remains "very active," while declining to discuss whether he is in settlement talks with Morgan Stanley, the bank that sources say is next in line for a settlement. A spokesman for Morgan Stanley also declined to comment.

He did welcome a decision last month by a state judge, Supreme Court Justice Marcy Friedman, rejecting Credit Suisse Group A.G.'s bid to dismiss his lawsuit accusing the Swiss bank of deceiving investors about the safety of mortgage securities that have suffered $11.2 billion of losses.

Mr. Schneiderman said the decision affirmed his power to pursue fraud cases under the state's Martin Act, a powerful law his office has wielded against Wall Street for more than a decade.

"It is a very clear statement of the law and the scope of our reach," the attorney general said.

Mr. Schneiderman said he is also confident about the Martin Act case he filed against Barclays P.L.C. last June, in which he accused the British bank of offering unfair advantages to high-frequency traders in its alternative trading system, or dark pool, while claiming to look out for less-favored clients.

At a hearing last month, state Supreme Court Justice Shirley Kornreich called the complaint "confusing" and "conflated," though she has yet to rule on Barclays' motion to dismiss it.

"This is a tremendously strong case," Mr. Schneiderman maintained in the interview. "It's not hard to figure out this was really egregious conduct."

He declined to say whether he would pursue other cases over dark pools but said "we expect to be active in this area."

Mr. Schneiderman said he is looking forward to a Feb. 24 civil trial in a nearly decade-old case over whether former American International Group Inc. Chairman Maurice R. Greenberg was responsible for accounting fraud at the insurer.