When the four delivery workers found the woman in the middle of the road, she was covered in so much blood that they couldn’t tell the color of her hair.

Whoever had done this to her, authorities said later, had stabbed 19-year-old Lizette Andrea Cuesta repeatedly, then thrown her out of a car near a remote, hilly road northeast of San Jose, leaving her for dead.

But she wasn’t.

And in the two hours between when Cuesta was found in Livermore and when she died Monday morning, she gave investigators evidence that could send the couple suspected of killing her to prison for the rest of their lives.

“Her internal fortitude, to stay alive and to fight, is pretty remarkable,” Sgt. Ray Kelly of the Alameda County Sheriff’s Office told the San Francisco Chronicle. “This young woman clung to life when she was left for dead and was able to live for another couple hours and get us that information. Ultimately that led us to these arrests.”

Authorities identified the victim, a resident of Tracy, Calif., on Tuesday evening.

They also announced the arrests of Melissa Leonardo, 25, and Daniel Gross, 19. The suspects, both from Modesto, were taken into custody on charges of murder. Leonardo was arraigned on a murder charge Wednesday afternoon, and did not enter a plea. Gross, whose murder charge also carries allegations of use of a deadly weapon and causing great bodily injury, had his arraignment continued to Thursday, according to the East Bay Times. Both remain in the Santa Rita Jail without bail.

Daniel Gross and Melissa Leonardo. (Alameda County Sheriff’s Office)

From jail, Gross told a reporter for KTVU, a Fox affliate, that he had sex with Cuesta in a car while Leonardo drove. Gross said he and Cuesta were later standing outside the vehicle when she elbowed him in the ribs and he snapped.

“It happened just like this,” he said, snapping his fingers for the reporter.

“I didn’t plan to do this at all,” he said. “I … hate myself, you know? I wish I could go back in time and that this never happened.”

Gross said he, Leonardo and Cuesta worked together at a Carl’s Jr. in Tracy, and that he and Cuesta shared an interest in skateboarding. The knife, Gross said, he had given to Cuesta for protection. He also told KTVU the three of them had smoked marijuana in the car that night, and that Leonardo had nothing to do with the violence.

After she was brutally stabbed, Cuesta had crawled nearly 100 yards — the length of a football field — to get to the road, where she had some chance of being seen by people in passing cars. That is where the UPS delivery workers found her.

Authorities determined the distance by measuring a trail of drying blood.

“You could tell it was so bad to where you just had to give her comfort,” Richard Loadholt, one of the UPS employees who had been riding with three other men on Tesla Road in Livermore around 2 a.m., told Sacramento Fox affiliate KTXL. Initially, he said he and his workmates thought she was missing an arm. “She fought like a soldier. Like a warrior.”

The hilly, winding road where she was found is a popular alternative to Interstate 580 for people traveling between Livermore and Tracy, according to Bay Area news station KRON. It was also virtually deserted in the predawn hours of Monday.

The area is so remote that the UPS workers had to send other people who had gathered at the scene to an area where there was better cellphone reception to call the police.

When first responders arrived, they decided that the best option was to airlift the dying woman to a hospital with an advanced trauma center. But as they tried to save her, investigators asked her questions. The most important one: Who did this?

“I’ve been around a long time, and I can only think of two to three times that I’m aware of in our agency that we’ve been able to get a dying declaration like that,” Kelly said.

In the legal world, a dying declaration is a statement made by someone who believes they will be dead soon. It’s an exception to the legal rule forbidding hearsay in court testimony, and it can hold tremendous sway in a case.

In this one, it led to arrests a few hours after the woman was declared dead.

About 10 a.m. Monday, the two suspects were arrested at a home in Modesto, about an hour from where the woman had been found.

“We were able to act on the information from our victim,” Kelly said.

The sheriff’s sergeant told the Modesto Bee that investigators recovered a “tremendous” amount of evidence at the home, thanks to Cuesta’s dying declaration.

“From the time we discovered Lizette to the time we got to Modesto was critical in the preservation of the crime scene,” Kelly told the Bee. “The evidence and Lizette’s statements to us helped make this investigation unfold very rapidly.”

A GoFundMe donation drive has been set up for Cuesta’s family.

This post has been updated.

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