MANDERSON, S.D. -- The Oglala Sioux Tribe Department of Public Safety said a "person of interest" is in custody in connection with the death of a teenager.

The body was found Friday north of Manderson, South Dakota. 

A missing alert was issued last Wednesday for 17-year-old Shayna Youngman Afraid of His Horses, but she had last been seen on Thursday the 3rd and last heard from on the 5th. 

A social media post by the department said the death is being investigated as a homicide by both tribal police and the FBI. 

Youngman Afraid of His Horses is the second missing woman whose body was found on the Pine Ridge Reservation last week.