Police arrested three women as part of an ongoing investigation on suspected Honolulu brothels fronting as massage parlors and “relaxation spas.”

Officers arrested Soon Woo Seo, 52, Hye Jin Jung, 37, and Jiyeon Hicks, 58, Wednesday after an Oahu grand jury returned an indictment Tuesday charging each with two counts of promoting prostitution and one count of illegal ownership of a business.

All were released after each posted $50,000 bail.

The arrests occurred around the same time authorities raided the Happiness Spa at 1666 Kalauokalani Way at 9 a.m., according to a source.

Law enforcement officers recovered evidence from the spa as part of the investigation.

The women were arrested at three different locations between 9 and 10:15 a.m. Police arrested Seo at a South Street address in Kakaako. A source told the Honolulu Star-Advertiser she is the owner of Happiness Spa.

Jung was arrested at a Kapiolani Boulevard address in the Ala Moana area.

Officers arrested Hicks at 1602 Kalakaua Ave. in Waikiki, the address of the Blue Star Spa, which the source said she owns. Her arrest is in connection with a February raid at the spa.

Brooks Baehr, spokesman of the Honolulu Department of the Prosecuting Attorney, declined to comment.