Authorities have released the first two autopsies of the 11 people found in a mass grave in the desert on the western edge of Albuquerque.

The results confirm that 31-year-old Cinnamon Elks and 22-year-old Michelle Valdez, both of Albuquerque, were victims of homicide.

The women's remains, along with those of Valdez's fetus and nine other adults, were found in February at a 92-acre construction site that was being leveled in preparation for a subdivision. Four of the victims have yet to be identified.

The two autopsies released Thursday by the state Office of the Medical Investigator say authorities were unable to determine a specific cause of death for Elks or Valdez, but they say the two were killed by "undetermined homicidal violence."

Valdez's autopsy said she suffered a head injury at the time of her death, but that the injury wasn't fatal.

"No injuries that might explain her death were found on extensive examination of the remains," the autopsies for both women said.

Valdez's body was released to her family this week and her funeral is scheduled for Friday, police said.

Her father, Dan Valdez of Albuquerque, reported her missing in 2005. She was last seen in September 2004 by her sister, who said Valdez told her she was going to California, the report said. Valdez had two children and was about four months pregnant when she died.

Elks last spoke with her mother on Aug. 20, 2004, and a missing persons report was filed on Dec. 15 of that year, the report said.

Elks and Valdez, along with several of the other victims, had a history of drug addiction and prostitution.

Albuquerque police began excavating the construction site in early February, when a hiker discovered a human bone. They sifted through 40,000 cubic yards of dirt before ending the dig 12 weeks later, saying they had recovered all the evidence they could.

Police say they are looking at other states for similar crimes that may help them solve the case.