JPMorgan Chase & Co said it may face federal enforcement actions stemming from two investigations into mortgage-backed securities that went bad in the financial crisis.

The largest U.S. bank, in a regulatory filing on Wednesday, said Securities and Exchange Commission staff told the company in January that they may recommend the commission bring cases against the company.

One possible case involves the bank's scrutiny and disclosure of facts behind two sets of mortgage securities, JPMorgan said.

A second investigation involves loans used in mortgage securities created by Bear Stearns, the investment bank that collapsed and was sold to JPMorgan in 2008.

The JPMorgan statements, included in an annual filing to the SEC, follow similar disclosures on Tuesday by Goldman Sachs Group Inc and Wells Fargo & Co.

The SEC staff frequently notifies subjects of investigations that it is weighing allegations of civil wrongdoing and offers them a chance to argue against legal actions.

The disclosures are the latest sign that government officials are stepping up action against banks that packaged home loans into bonds during the housing boom. The underlying mortgages later soured, spurring billions in losses for investors.

JPMorgan also disclosed that it is responding to questions from various government entities involving the October 31 collapse of commodities firm MF Global Holdings Ltd. JPMorgan handled MF Global accounts which have been at the center of searches for more than $600 million in missing funds that belong to MF Global customers.

The bank said it is a defendant in six different private lawsuits over its actions in the MF Global collapse. It said it has also been sued in another case over its role in selling bonds for MF Global in February and August 2011.

JPMorgan listed the MF Global cases among matters it considers material to the company. The bank has said in the past that it faces more than 10,000 lawsuits on assorted claims.

JPMorgan raised slightly its estimate of reasonably possible losses it may suffer beyond its litigation reserves to as much as $5.1 billion, up from $5.0 billion at the end of September.

The bank said it recorded $4.9 billion of litigation expenses in 2011, up from $7.4 billion the year before. It earned $19 billion in 2011.

(Reporting by David Henry in New York; editing by John Wallace, Dave Zimmerman)