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The haunting images of 11 women stare back from the City of Albuquerque website as if to remind the world that five years after their bodies turned up in a mass grave on the outskirts of town, a killer likely remains on the loose.

It was early February 2009 when Christine Ross, walking her dog Ruca in a field atop a mesa, spied what turned out to be a human femur. By the time authorities were done excavating the 92-acre site -- once dubbed the biggest crime scene in American history – 11 sets of remains had been unearthed. The victims were all females between the ages of 15 and 32, and had a history of drug abuse, prostitution or both.

In the last half-decade, connections to other mass killings have been investigated and dismissed, and suspicion has focused on various drifters and criminals only to see them cleared. Authorities insist they won’t stop until they solve what is known locally as the “West Mesa murders.”

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“This case will not be shelved or classified as a cold case, it will remain open until a prosecutable case can be presented to the district attorney’s office,” Cmdr. Anthony Montano, of the Albuquerque Police Violent Crimes Division, pledged to FoxNews.com.

The victims have all been linked to a stretch of the legendary Route 66, known as East Central Avenue where it passes through Albuquerque. The roadway is lined by seedy motels and fast-food joints, and known for the low-rent liaisons that take place in cars and rooms for rent. The names of the victims, who all disappeared between 2003 and 2005, are all but forgotten, except to the families and investigators who have endured the painstaking process of sifting through more than a thousand tips that eventually dwindled.

Montano wants to keep his department’s biggest unsolved crime in the forefront of people’s minds, knowing that his best chance for a break will come from a tipster. Someone who either heard or saw something involving the red dirt mesa, which also yielded the remains of a fetus.

“We are working [with local government officials] to erect a memorial site in honor of the victims,” Montano said.

Montano made it a point to reach out to the families of victims last week to provide updates on the investigation, knowing the approaching fifth-year anniversary of the mass grave’s discovery would be on their minds. All but three of the victims' families attended.

“They appeared to walk away from the meeting with a greater understanding of our investigation and were genuinely appreciative for bringing all of them together,” Montano said.

One mother still seeking answers and justice is Diana Wilhelm. Her daughter, Cinnamon Elks, was 32 when she disappeared. She said her grief dates back another five years, to when her troubled daughter disappeared.

“I know it’s the five-year anniversary, but this has been a much longer road for us,” Wilhelm told KRQE.

Elks “sank into the abyss of addiction” before fading out of her family members’ lives. Investigators estimate she was killed between 2004 and 2005, around the time police began investigating a disturbing trend of missing prostitutes. Her story is typical among the troubled women whose remains were found in the grave. Many were reported missing, but pinning down the exact year when they disappeared proved impossible in some cases, due to their transient lives.

The case continues to shock the residents of Albuquerque, a relatively peaceful and safe city of just over half a million people. But women like those found on the mesa have long been easy targets for serial killers and gangs. Just three hours south, in Juarez, the unearthing of more than 600 women over a 10-year span made headlines. Montano says there is no connection whatsoever between the Albuquerque case and the Juarez femicide.

“Unfortunately these types of cases -- similar backgrounds -- are sometimes more common than we would like to believe," Montano said. “When it comes to this type of victimization it doesn’t matter where it happens, it is what is available to the perpetrator and all circumstances vary.”

A study by Purdue University researchers found that serial murders have declined, but when they do occur, victims are increasingly likely to be prostitutes. A year after the bodies at West Mesa were found, a similar mass grave containing the remains of six women was discovered 2,000 miles away on Long Island, N.Y.  Authorities probed a possible connection between the Albuquerque case and what became known as New York's “Gilgo Beach Murders,” but determined there is no connection.

But the cases bear similarities, and have one troubling aspect in common: They remain unsolved.

“We are not commenting further at this time on the Gilgo investigation until/unless we have some additional information pertaining to the investigation that serves the public by its release,” Suffolk County Police Deputy Inspector Kevin Fallon told FoxNews.com.

Montano said there are suspects in the case his investigators are handling, but so far, there is nothing prosecutable. Over the last five years, Albuquerque detectives have looked into dozens of locals who may have had a propensity toward violence against women. There has been speculation police have a dozen potential suspects, but two names recently emerged in a KRQE News television report. Montano blasted the report as irresponsible and said it could have jeopardized the investigation.

Of the two men, one is dead. He was shot and killed in December 2006 by a pimp who accused him of strangling one of his prostitutes. The other is serving a prison term on a 2010 sex charge. In 2013, a grand jury indicted the man, now 56, on nine counts of first-degree criminal sexual penetration and four counts of kidnapping with great bodily harm.

A reward of up to $100,000 is being offered for information leading to the arrest and conviction of the person or persons responsible for this crime. They believe the key to solving the crimes lies in the seedy strip where the victims were often seen.

"Investigators would like to hear from women who may have been working the streets of Albuquerque between 2001 and 2005, or anyone who may have solicited the victims during that period of time," police said in a statement..