At 6:30 a.m., authorities say the two women were on the side of the highway changing a flat tire when they were struck by the semi.
The victims were identified as 48-year-old Shun Jones of Carrollton, Texas and 38-year-old Amanda Omo-Iyamu of Balch Springs, Texas.
The truck was going westbound on Interstate 70 just east of Limon.
Omo-Iyamu died on the scene. Jones was airlifted to a hospital and later died.
Jones' son, Lamarcus Lockett II, says he was inside the car as his cousin and mother tried to fix a flat tire on the car. He had also tried helping, but they couldn't quite fix it, so he went inside the car to call 911.
"The truck just came out of nowhere," Lockett said. "I just saw my cousin flying [and] my mama flying."
Lockett said he was able to see his mother in the hospital later that morning.
"I just saw my mom laying there," Lockett said. "She [didn't] even feel like she was cold. Her eyes didn't even roll back. They were still brown. I kissed her."
The semi truck pulled over about half a mile away from the crash scene, according to Sgt. Mike Baker with Colorado State Patrol.
According to CSP, the occupants of the semi were an adult male and a juvenile male.
According to officials, prior to their arrival at the scene, the juvenile was transported from the scene by a private party.
When law enforcement arrived, the adult male, Michel Martin, 37, told them he was driving the semi truck. However, upon further investigation, the juvenile was determined to have been the driver.
The 16-year-old was on his way to a high school rodeo competition in Wyoming, according to his aunt, who spoke to 9News by phone Sunday afternoon.
"He's going to have to live with this for the rest of his life anyway," said Jessica Gunter, the 16-year-old's aunt. "That's enough punishment for a 16-year-old. Even though it was an accident, he'll have to live with it. And that's not an easy thing."
Lockett says he is angry that a 16-year-old was behind the wheel.
"I'm strong enough to forgive him," Lockett said. "But, I'm not going to forget."
"My mom was a care-giving woman," Lockett said. "She [didn't do] nothing but love people."
The juvenile driver was charged with two counts of failing to remain at the scene after an accident involving death, which is a felony. He was also charged with two counts of careless driving caused death, which is a misdemeanor.
Martin was charged with one count of false reporting, which is a misdemeanor.
Both were booked into the Lincoln County Jail, as of Saturday night. On Sunday, the 16-year-old's aunt told 9News the two had bonded out and had a court appearance scheduled for Monday morning.
Police say alcohol and drugs are not believed to be contributing factor in the crash.
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