Myrtle Beach- Horry County police made four arrests on charges of prostitution in an undercover investigation into illegal activities at local adult entertainment businesses.

According to a news release issued Monday by the Horry County Police Department, detectives arrested four women on the prostitution charges, with one lady also facing an additional drug charge. The undercover operation began March 16. It was not yet clear when the arrests were made.

According to police, those arrested on prostitution charges were:

-- Amber Johnson, 23, arrested at Secrets

-- Maria Ruiz, 31, arrested at Tropical Beauties

-- Ange Greene, 22, arrested at Fantails

-- Amber Gregory, 28, arrested at Nuttin Butt Horseplay (she also faces a charge of possession of cocaine

All four women are in J. Reuben Long Detention Center awaiting a hearing about bail.