INDIANAPOLIS, Ind. – Indianapolis Metropolitan police raided multiple locations related to massage parlors Tuesday in connection with a federal investigation into human trafficking.

The raids are part of a year-and-a-half long investigation that spans from Indianapolis to Greenwood to New Albany. It was in coordination with Homeland Security, the FBI and ICE.

The IMPD operation concentrated on at least eight locations around the city, including the south side, west side and northwest side. The raids were at six massage parlors and at least two residences.

Inside the locations, officers found at least 12 women. Investigators say the women were from China, and likely trafficked into the U.S. through the Canadian border.

The women are believed to have been forced to work, some of them through prostitution at the parlors to pay off debts for being brought over into the U.S.

“In this case the girls lived in the massage parlors they normally sleep on a massage table & they have a very small living space, they have very few assets,” an undercover officer told CBS4.

Investigators said they also confiscated thousands of dollars in cash and some drugs at the locations. At a location on S. East Street, police not only found women, they also seized $30,000 hidden in detergent bottles.

Police also served search warrants at two homes in Speedway. They say they are now working to track down who was behind the operation.

No arrests have been made as of Tuesday afternoon. Police says the women they found will be treated as victims and work with advocates from Ohio to get help.