The investigation that led to the indictments started more than two years ago when St. Paul police officer Gerald Vick discovered an enterprise that brought women from central American and Caribbean countries to Minnesota.
Vick was killed while working undercover in May 2005, in a confrontation outside a bar.
Nancy DiPerna, the assistant St. Paul police chief, says officials determined that Vick's investigation into human trafficking needed to continue, but that St. Paul couldn't go it alone.
"The St. Paul police, recognizing that we neither had the resources nor the reach to pursue the investigation alone applied for a federal grant that resulted in the formation of the Gerry Vick human trafficking task force," she said.
The Department of Homeland Security called the indictments part of an on-going, complex, multi- law enforcement investigation.
U.S. Attorney Rachel Paulose says federal officials linked the prostitution ring to activity in 30 states. Eight brothels in Minnesota were located in Minneapolis, Richfield, West St. Paul and Austin.
Paulose said the 25 individuals arrested conspired to lure women from other countries to the U.S. and then to Minnesota, took their passports and put them to work:
"Once here, the defendants housed the women in brothels where the women had to perform commercial sex acts for the monetary benefit of the defendants," she said.
Paulose says the alleged head of the operation, Marisol Ramirez, promoted the operation with business cards written in Spanish that advertised the brothels.
The indictments were connected to Saturday's raid in south Minneapolis, an area home to many Hispanic residents. Some immigrant advocacy groups argued that police and immigration were targeting the area for undocumented workers, not prostitutes, because immigration officials participated in the raid.
The U.S. attorney's press release did list the immigration status of the accused. Eighty percent were undocumented.
An expert on immigration law, University of St. Thomas professor Virgil Wiebe, says he expects to see more criminal raids targeting immigrants as the the president calls for liberalizing some of the immigration laws.
"I think the administration wants to be seen as being aggressive on immigration enforcement at the same time it's trying to work with Democrats to find an answer to the large undocumented workers in the United States," he said.
Paulose's news conference was her first since three attorneys in her office resigned their management duties. And two weeks ago Attorney General Alberto Gonzales told a House committee he had concerns about Paulose and that he would consider replacing her if her performance did not improve. However, Paulose declined to answer questions about management of her office.