SIOUX CITY -- Matt M. Dummermuth resigned his position as U.S. Attorney for the Northern District of Iowa Tuesday after serving in the position for nearly three years.

"I'm grateful for the opportunity I've had to pursue justice and uphold the rule of law," Dummermuth said in a statement released Tuesday. "It has been a wonderful privilege to serve and protect the people of Iowa."

Stephanie M. Rose was sworn into office Tuesday to replace Dummermuth. The statement said that Dummermuth, a native of Elgin, Iowa, plans to spend extra time with his family and help on his parents' farm before taking on his next professional challenge.

During his tenure as U.S. attorney, Dummermuth implemented a prosecution and prevention strategy for child exploitation crimes. His office charged and convicted record numbers of defendants in the Northern District for child pornography production, distribution and possession and for enticement and travel-related child exploitation crimes, the statement said.

Dummermuth also led a work-site enforcement prosecution effort at a meatpacking plant in northeast Iowa where 389 illegal aliens were arrested. His office prosecuted 305 of those defendants for immigration and document fraud crimes.