The government opened a new front in its probe of financial firms’ dealings in the mortgage market, filing civil fraud charges Monday against an investment adviser and his firm in connection with complex securities during the 2007 housing bust.

The Securities and Exchange Commission accused Thomas Priore and ICP Asset Management of fraudulently managing the securities in a way that cost investors tens of millions of dollars. The SEC also said Priore and the New York firm he owns and heads as president improperly reaped millions in fees and undisclosed profits at the expense of clients.