U.S. Attorney John Walsh is stepping down as Colorado’s top federal prosecutor.

Walsh, who served for six years, announced his departure Friday. He will return to private practice, where he worked for more than a decade before his appointment in 2010.

Attorney General Loretta Lynch lauded his work on a team of state and federal officials who helped reach major settlements with the big banks after the financial crisis, including a $7 billion settlement with Citigroup. She says Colorado is a safer place because of his prosecutions of organized crime, drug cartels and gang violence.

Walsh says it was a high honor to serve as leader of the attorney general’s advisory committee, offering policy guidance to federal prosecutors across the country.