The more they dig, the more bodies they find.
Albuquerque, N.M., police are preparing for what they say could be the biggest homicide investigation in the city's history as investigators look into who buried bodies -- 11 so far, including a first trimester fetus -- in the ground in a wide expanse of desert mesa.
"There are several people of interest … that the department is looking at," Albuquerque Police Officer Nadine Hamby told ABCNews.com today.
So far, only three of the bodies have been identified, the most recent being 22-year-old Michelle Valdez and her fetus. Remains of the 11th body were found Tuesday.
Valdez's father, Daniel Valdez, told ABC's Albuquerque affiliate KOAT that he reported his daughter missing in February 2005 and that as information about the rising body count hit the news, he feared his daughter would be among them.
"It's hard to remember back to the last time I hugged her and, as always, wishing I'd been able to hug her more," he said.
Valdez was arrested in the area numerous times on various charges, including drug possession, prostitution and assault. She was also transferred to Arizona on a prostitution charge in April 2003, according to the Bernalillo County Metropolitan Detention Center in Albuquerque.
Daniel Valdez told KOAT that his daughter had a drug problem, and he was trying to get help for her before she disappeared.
Hamby said the investigation had put a huge strain on the department, but the digging will not stop until investigators are satisfied they've recovered all the human remains they can find. There are currently more than 20 people who have been reported missing from Albuquerque.
"At any given time, there's 20 to 30 officers," she said.
Not all of them are digging. Some are on security detail, a necessity after civilians started showing up at the property, some apparently carrying shovels and prepared to dig themselves, Hamby said.
The department is also receiving assistance from the FBI and state police. While much of the digging has been done with hand tools, Hamby said, police are also using a bulldozer, satellite images and an infrared device that allows searchers to locate objects under the dirt.
The first bit of remains -- a bone sticking out of the dirt -- was found Feb. 2 by a woman walking her dog around the property that had been prepared for a new housing development. A team of police officers, anthropologists and forensics experts have been out on the 92-acre west mesa every day since.
Hamby said the remains have all been found within "a few acres" of one another. Once police clear an area, they expand farther out.
When bones are found, they are sent to New Mexico's Office of the Medical Investigator to determine whether they belong to a known victim or someone new. Only four skulls have been found so far.
The only complete skeleton has been that of 34-year-old Victoria Chavez, a sometime prostitute who was last seen in 2003 and reported missing in March 2004.
Both Valdez and Chavez were identified through dental records, Hamby said.
"I was in denial," her mother, Mary Gutierrez, told ABCNews.com earlier this month of the day she learned the bones were her daughter's. "I said, 'You must be wrong.'"
Gutierrez said her daughter was funny and outgoing and was working to clean up her life in the months before her disappearance.