OMAHA, Neb. (AP) — Federal authorities have indicted a fifth person who prosecutors say used spas as fronts for a prostitution operation in Omaha.

Federal prosecutors say the spas attracted customers from the Omaha area, elsewhere in Nebraska and from other states.

The prosecutors say 45-year-old Kimberly Bivens, of Omaha, pleaded not guilty on Wednesday to a conspiracy charge.

The other four are 63-year-old William Knox, of Omaha; 41-year-old Tammy Schuck, of Omaha; 31-year-old Christopher Tierney, of Omaha; and 22-year-old Tabatha Ashburn, of Junction City, Kan.

All four have pleaded not guilty to conspiracy and other charges.

Trial dates haven’t been set.