Rigoberto Alvarado (Courtesy Sweetwater County Sheriff's Department)

Law enforcement officials in Rock Springs say they are focusing on four different areas in their investigation of the murder of 17-year-old Rigoberto Alvarado, whose body was found in a shallow grave outside Rock Springs on August 19 . Those areas include the timeline of Alvarado’s death, interviews, forensic evidence and the cause of death.

Sweetwater County Sheriff Rich Haskell and Chief Mike Lowell of the Rock Springs Police Department said on Friday Alvarado’s father, Rigoberto Alvarado, Sr., reported his son missing to the Rock Springs Police Department on the morning of July 30, when he did not return home after leaving the family’s home the night before.

Investigators  say they have identified several people who were in Alvarado’s company that night.110-plus interviews have been conducted by city and county detectives since Alvarado’s disappearance.  Polygraph examinations have come into play, and one person who was scheduled for a polygraph failed to show up for an appointment.

Detectives and crime scene technicians have collected hundreds of items of evidence in the case thus far, including DNA evidence, all of which has been submitted to the Wyoming State Crime Laboratory in Cheyenne for forensic examination and analysis. According to detectives, Alvarado suffered several types of violent injury, any one of which could have been the cause of death.  The nature of those injuries is being withheld for the time being while the forensic examinations are ongoing.

Alvarado, whose family moved to Rock Springs from the Pomona, California, area, attended  Rock Springs High School. A $5,000 reward is being offered for information resulting in the arrest and conviction of the person or people responsible for his death.  Anyone who has such information is asked to contact either the Rock Springs Police Department at (307) 389-0264 or the Sweetwater County Sheriff’s Office at (307) 350-4010.