U.S. prosecutors have abandoned their case against Angelo Mozilo, a pioneer of the risky subprime mortgages that fueled the financial crisis, after a two-year quest to bring a civil suit against him.

The Justice Department has decided not to sue Mozilo, the co-founder of Countrywide Financial Corp., according to people familiar with the matter. That effectively ends nearly a decade of U.S. scrutiny of a man who became a face of risky lending practices and later an emblem of the government’s mixed success in holding individuals accountable.