Crime Despite Dozens of Confessions to 1991 'Austin Yogurt Shop Murders' of 4 Teens, the Case Remains Unsolved A new episode of "People Magazine Investigates" examines the unsolved murders of Eliza Thomas, 17, Jennifer Harbison, 17, Sarah Harbison, 15, and Amy Ayers, 13 By Emily Palmer Emily Palmer Emily Palmer is a Senior Crime Writer at PEOPLE, where she has been a reporter since 2023. Her work has frequently appeared in The New York Times. She has also been published in The Boston Globe, Cosmopolitan Magazine and ELLE Magazine. People Editorial Guidelines Published on August 17, 2023 10:17AM EDT Eliza Thomas, Sarah Harbison, Amy Ayers and Jennifer Harbison (from left to right, top to bottom). It took just minutes to quell the blaze at the “I Can’t Believe it’s Yogurt” shop in Austin, Texas, on December 6, 1991. But then, as the smoke cleared, firefighters discovered three bodies: naked and heaped beside each other, their flesh burned out in the storage room. The teenage girls were later identified as Eliza Thomas and sisters Jennifer and Sarah Harbison. A fourth body was found about 10 feet away, Amy Ayers, just 13, lying flat on her stomach, her right hand reaching. The next day, law enforcement officials promised to find the girls’ killers. Some 30 years later, they’re still looking. People Magazine Investigates dives into the unsolved case in its upcoming episode titled “Who Killed Our Girls?” airing on ID and streaming on Max Monday, Aug. 21, 9/8c. (An exclusive clip is shown below.) Over the years, dozens confessed to the quadruple homicide but were released, their stories of guilt just that: stories. Rife with false confessions and lacking in DNA matches, the case of the so-called Yogurt Shop Murders has lacked all but suspects (more than 1,200) and included the arrest of four boys twice — years apart. Billboards like this one were placed all over the city in the aftermath of the murders, which Amy Ayers's brother, Shawn Ayers, tells PEOPLE “changed Austin overnight.". David Kennedy/Austin American-Statesman-USA TODAY NETWORK Police believe that as Eliza and Jennifer, who worked at the yogurt shop, were closing for the night, at least two men forced the four girls into the storage room, made them strip, bound them in their own underwear, raped some of them, shot them each in the back of the head and then set fire to the shop — burning away most evidence. Inside the burned-out yogurt shop in 1991. Courtesy Tony Garcia Police ultimately centered on four White teenage boys – Maurice Pierce, Michael Scott, Robert Springsteen and Forest Wellburn – detaining and questioning them on and off for years, ever since Pierce was arrested with a .22-caliber pistol shortly after the murders and confessed. (Police ultimately didn’t believe him and let him go.) Then the Mexican government announced they had arrested a man known as “the Terminator” in October 1992. Porfirio Villa Saavedra ran the Mierdas Punks motorcycle gang, matched the description of a man seen in a car outside the yogurt shop that night and had confessed. (Villa Saavedra quickly said Mexican law enforcement had tortured him into the confession, and he was ruled out as a suspect.) The open investigation into the four girls's murders has dragged on more than 30 years. No one is currently in custody. American-Statesman-USA TODAY NETWORK The four boys were rounded up again in 1999. This time Scott and Springsteen both confessed to the slayings. Scott was placed on death row in 2001 and Springsteen sentenced to life behind bars a year later. But the convictions didn’t hold: the Texas Court of Appeals ruled that the men should have been given the chance to cross-examine each other. There were other problems with the case: A detective had held a gun to Scott’s head during his pivotal multi-day interrogation, and another detective admitted to withholding key information for a year and half: Pierce’s gun had all but been ruled out as the weapon used in the girls’ murders. Investigators dredged the Colorado River looking for another gun supposedly dumped there almost a decade earlier but didn't find it. Later, new and improved DNA tests came back without any matches. Scott and Springsteen were released on bond in June 2009 and their charges were dismissed. Want to keep up with the latest crime coverage? Sign up for PEOPLE's free True Crime newsletter for breaking crime news, ongoing trial coverage and details of intriguing unsolved cases. No one has since been arrested in the case– although that DNA test picked up genetic material from an unidentified man: possibly the actual perpetrator. The FBI has a matching sample but refused to provide it to Austin investigators in 2017, citing legal complications. People Magazine Investigates: Who Killed Our Girls? airs on ID and streams on Max Monday, Aug. 21, at 9/8c.