Securities regulators sued former top executives at Fannie Mae and Freddie Mac on Friday, saying they misled investors over exposure to risky mortgages.

The U.S. Securities and Exchange Commission sued three former executives at Fannie Mae and three at Freddie Mac, including former chief executives of both companies. The civil charges were filed in two separate lawsuits.

Three former Fannie Mae executives – former Chief Executive Officer Daniel H. Mudd, former Chief Risk Officer Enrico Dallavecchia, and former Executive Vice President of Fannie Mae’s Single Family Mortgage business, Thomas A. Lund – were named in the SEC’s complaint filed in U.S. District Court for the Southern District of New York.

The SEC also charged three former Freddie Mac executives – former Chairman of the Board and CEO Richard F. Syron, former Executive Vice President and Chief Business Officer Patricia L. Cook, and former Executive Vice President for the Single Family Guarantee business Donald J. Bisenius – in a separate complaint filed in the same court.

The SEC said both firms have agreed to cooperate with the agency and have entered into non-prosecution agreements.

Freddie Mac and Fannie Mae have been propped up by about $169 billion in federal aid since they were rescued by the government in 2008.