CORPUS CHRISTI, Texas — It was a high-profile murder case that stunned the entire community. The half-sister of a local state representative was found dead, her body dumped on the street of a westside neighborhood.

For the first time in 11 years, 3News is hearing the details that helped solve the case, and in a surprising twist, how detectives learned it wasn't the suspect's first victim.

"You don't want to commit homicide in Corpus, because there is a good chance of you getting caught," retired Corpus Christi Police Department Lt. Isaac Valencia said.

The case began on Dec. 28, 2008.

"It was a cold night arriving on the scene. We pulled up on it," Valencia said. "The first thing you see when you pull up with the headlights was a body, pretty much naked in the street."

A young woman, beaten and strangled to death, was found by a passerby on Bluebonnet Drive.

It was the beginning of a murder investigation.

"This is the one when you show up on the scene," Valencia said. "This is your baby and you have to figure it out."

"Take your fingers and frame the scene, and you look at it, and then he tells me the thing that really stops your heart.  You see that? That's all we got," Valencia said.

It's a call retired Corpus Christi Police Department Lt. Isaac Valencia will never forget -- his first as the homicide supervisor with CCPD.

More than a decade later, details on the case flooded back as he spoke with 3News.

"We had the body, in the process of being out there, with new technology in the cars, we saw what appeared to be the shape of a peanut," Valencia said.

That mark was a tattoo. A list of names was narrowed down with the use of a mobile database that was fairly new technology at the time.

"That's the nickname on the street, 'Peanut,' and that's the name of the person," Valencia said.

The victim was 29-year-old Devon Herrero.

"Then you realize, 'Oh my God, we know the person,'" Valencia said.

They had a name, and then a witness.

"When we started canvassing the neighborhood, one of the neighbors contacted said they heard the loud muffler of a truck," Valencia said.

It was a detail that would end up being useful later in the investigation.

The team continued to reach out to those who knew Herrero. The next day, they checked bus stops along Leopard Street, speaking with those who knew "Peanut." All were outraged when they found out she had been killed.

"One of the females said they had just been with her that night, literally within an hour of the last time she was seen alive," Valencia said.

What she said next would crack the case wide open.

"She asked, 'You want the number?'" Valencia said. "I said, 'Excuse me?'"

Court documents say the woman told police that Herrero had called a phone number at 2:25 a.m. the day she died, and that a guy with lots of tattoos had picked her up in a truck. It was a number that would eventually lead detectives to Esteban Ruiz, a man who turned out to own a truck with a loud muffler. He lived just one block away on the same street where Herrero's lifeless body was found.

A check of Ruiz' home revealed more.

"They found some burned stuff on the ground. Whatever he was burning, he had not completely burned, and remnants were still visible, of what her last clothing looked like," Valencia said.

It furthered the case.

"All this within less than 36 hours of actual work time," Valencia said. "Less than 36 hours, from the start to nailing who it was."

Ruiz turned himself in to police after a warrant for his arrest was issued. The charge was murder. He eventually received 40 years in prison for the crime as part of a plea deal.

However, as Ruiz began to serve his time behind bars, there was a shocking new discovery.

"What stood out about this is, I believe he was a serial killer," Valencia said.

Find out about another murder at the hands of the same man, and how police were able to pin Ruiz with the crime, in True Crime: Catching a Killer Pt. 2 - A 3News Special Report.