Officials gave notices to the seven businesses that they would have their licenses rescinded within 30 days.
Authorities served the warrants at about 12:30 p.m. without incident. Police were looking for evidence of prostitution, such as condoms, sex toys and ledgers keeping track of the under-the-table business, Manley said.
Officers found several municipal code violations, including employees not licensed as massage therapists, mislabeled tools or massage oils with no labels at all.
One of the businesses had a table shower, where the customer lies down nude while the employee washes him or her. Another room had a typical massage table, a sink, a cabinet full of sheets and a single bottle of a liquid with "massage" handwritten on it.
There were no arrests Friday. Instead, some of the business owners and their employees would be issued court summons, Manley said.
Prosecutors have already filed charges against several of the business owners, officials said.
Immigration and Customs Enforcement agents were also on hand to investigate possible human trafficking.
Almost all of the workers and store owners are Chinese or Vietnamese, Manley said.
Any employees who appeared to be victims of human trafficking would be treated as such, he added.
Costa Mesa police had been fielding complaints on the location for years. Last June, detectives decided to ramp up their investigation.
Police interviewed customers and sent in undercover officers to investigate the alleged prostitution.
"These weren't just isolated incidents," Manley said.
The property owner was not immediately available for comment and left shortly after police arrived, officials said.
