A California teen stabbed and left for dead on the side of a road before dawn Monday crawled nearly 100 yards to find help and used her final moments to point police toward her alleged killers, investigators said.

Four UPS delivery drivers carpooling to work around 2 a.m. spotted the victim, identified by Alameda County Sheriff's Office officials as Lizette Andrea Cuesta, 19, of Tracy, on the side of a road near unincorporated Livermore, located about 50 miles east of San Francisco.

Cuesta was soaked in blood, with injuries so severe that the UPS workers initially thought she was missing an arm, Sgt. Ray Kelly with the Alameda County Sheriff's Office told the San Francisco Chronicle. She was airlifted to Eden Medical Center in Castro Valley, where she died about two hours after being found.

She gave police officers a “compelling account” of the brutal attack in that short time, Kelly said.

Cuesta’s account led investigators to Modesto, where they arrested Daniel Lee Benjamin Gross, 19, and Melissa Jill Leonardo, 25, on murder charges. Both are being held in the Santa Rita Jail.

Kelly told the Modesto Bee that a "tremendous" amount of evidence was found at the couple's home. He credited Cuesta's statements to officers with moving the case forward so rapidly.

"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

"Her internal fortitude to stay alive and to fight (was) pretty remarkable," Kelly told the 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."

Kelly said he can recall only a handful of times that his agency has been able to get a "dying declaration" from a victim. According to Cornell Law School, a dying declaration is a statement made by a witness -- later unavailable at trial -- who made the statement under the belief that their death was imminent, and the statement concerns the cause or circumstances of that impending death.

A dying declaration is admissible in court as an exception to the hearsay rule of evidence.

"A dying declaration is a very compelling piece of evidence that's recognized in the court to be very credible and reliable information," Kelly said.

Investigators said that Cuesta was stabbed repeatedly and thrown from a car, according to the Washington Post. She dragged herself the length of a football field so passing motorists could see her lying there.

Officers could tell how far she dragged herself because of the blood trail she left behind, the Post reported.

Richard Loadholt was one of the delivery drivers who found Cuesta. He told Fox 40 in Sacramento that there was so much blood that he couldn't tell what color the girl's hair was.

"You could tell it was so bad to where you just had to give her comfort," Loadholt told the news station. "Anything else was gonna be painful."

While another driver who happened upon the scene went to find a location with better cellphone reception for a 911 call, Loadholt and his colleagues urged Cuesta to stay awake and keep talking to them.

"She laid down for almost three minutes at one period, and we told her to get up," Loadholt said. "She knew she had to get up, and I commend that.

“She fought like a soldier. Like a warrior.”

Roberto Cuesta, the victim's uncle, told CBS Sacramento that his niece's death "goes beyond words." Lizette, who was originally from San Jose, was living in Tracy with her father when she was killed.

A vigil was held Tuesday night at a San Jose skate park where the teen was a fixture.

Her father, Ray Cuesta, said he last saw his daughter on Sunday. He said he is proud of his daughter for the strength she showed even in death.

"I love her," Ray Cuesta told the news station. "She was always a fighter, she was always brave, strong, a leader. If she wanted to do something, she would get it done."

Investigators believe that Cuesta got into the car with Gross and Leonardo willingly. Kelly described her as a friend of the couple, whose Facebook pages indicate they are engaged.

The motive for the attack was not clear.

Ray Cuesta said that, despite her death, he feels like his daughter won the battle against her killers.

"I mean, I know she passed away, but when they did this to her, they figured, you know, they got away with it," Cuesta said. "And she didn't let them get away with it. She brought peace to herself, and she brought peace to me and my family."