The man accused of kidnapping 15-year-old Gabrielle Swainson is also being questioned in the disappearance of a 28-year-old woman in September.
Richland County Sheriff Leon Lott said Tuesday that Freddie Grant, 52, was last seen with Adriana Diana Laster on September 3, 2011 in Elgin.
Lott said it may be more than a coincidence that another young female who looks similar to Gabbiee is missing.
Laster was reported missing in March by a family member in Homestead, Florida.
Laster is described as a black female, standing 5'4", weighing 120 pounds. She has black hair and brown eyes.
The FBI, Richland County Sheriff's Department, and Kershaw County Sheriff's Department are working with the Elgin Police Department and Florida authorities on her disappearance.
Grant is in custody in the Lexington County Detention Center. He has not been charged in connection with Laster's disappearance.
If you know anything about Laster's disappearance, you are urged to call Crimestoppers at 1-888-CRIME-SC.