Kaitlynn Cargill was believed to be involved in a drug deal at the time of her murder.
A 16-year-old boy is suspected of carrying out the crime with a hammer and has been charged.
Cargill first went missing on June 19 when walking her dog near her home in Bedford.
Two days later, her body was found in the Texas landfill.
According to a medical examiner, her death was first suspected to be the result of 'homicidal violence'.
It is believed Cargill met with the accused suspect at a nearby apartment for drugs before he attacked her in his apartment.
A crime scene expert found '“small areas of what appeared to be blood spatter along the hallway walls and several doors inside the apartment to include tile bathroom door, bedroom that [the teen] stays in and the hallway closet door,”
The hammer found at the scene is believed to contain the young victims DNA.
Police have since said in a statement: 'The juvenile was detained and has been taken to the Tarrant County Juvenile Detention Facility in Fort Worth.'