Investigators have identified a suspect in a Texas quadruple cold case murder more than three decades old. Police in Austin said on Friday that they had linked Robert Eugene Brashers to the murders of four teen girls at a yogurt shop in 1991 through DNA. Brashers, who committed suicide in 1999, was also suspected of being a serial predator at the time, according to the Austin American-Statesman. He was convicted of attempted murder after shooting a woman in the head in 1985, and was sentenced to 12 years in prison. He was released in 1989, however, after only serving three years in prison, the Statesman reported. BRYAN KOHBERGER SAYS HE WAS DIAGNOSED WITH 4 MENTAL DISORDERS BEFORE GUILTY PLEA: REPORTHe fatally shot himself following a police standoff at a motel where he had been hiding with his wife, daughter and two stepdaughters, after releasing them from the motel. DNA evidence also linked Brashers after his death to three rapes and murders in Missouri and South Carolina – including a mother and daughter – and a rape in Tennessee. Robert Springsteen and Michael Scott, who were teenagers at the time of the murders, were charged and convicted of the killings in 2001 and 2002. They were sentenced to death and life in prison respectively, but their convictions were overturned on appeal, including because no DNA evidence linked them to the crimes. What became known as the "Yogurt Shop Murders" remains infamous in Austin as one of its most violent cases, and is still open. HBO premiered a docuseries called "The Yogurt Shop Murders" last month about the killings. Amy Ayers, 13; Eliza Thomas, 17; and sisters Jennifer and Sarah Harbison, ages 17 and 15, were bound, gagged and shot in the head at the "I Can’t Believe It’s Yogurt" store where two of them worked. The building was then set on fire."Our team never gave up working this case," Austin police said in a statement on Friday. CLICK HERE TO GET THE FOX NEWS APPThe department has a news conference planned on Monday to discuss the new evidence in the case. The Associated Press contributed to this report.