The 911 call was revealed days after 2-year-old Isaiah Weitzel was left in a body cast.
A harrowing 911 call is exposing grim new details of a Colorado car crash that left a 2-year-old boy seriously injured, all because authorities say a driver didn't want to be a father.
Read: Toddler Left in Body Cast After His Dad Tried to Kill Him by Intentionally Crashing Car: Cops
Isaiah Weitzel was seriously hurt after police say his 29-year-old father, Nathan, deliberately crashed his car at 75 mph into two parked vehicles.
The boy was not in a car seat and wasn't even wearing a seat belt. Witnesses say they were shocked to see the father was not comfort his injured son but actually hitting him in the August 21 incident.
A bystander called 911 reporting to the dispatcher: “Yes there's a person inside. His head is down. I hear a baby crying.”
The 911 operator asked: “Do you know how old the baby is?”
“It looks like two or three. The baby has blood on him. Oh! Oh! Oh! The man's hitting the child who's crying so call social services too,” the shocked caller said.
The stunned operator asked: “Wait. Why is he doing that?”
“I guess the baby's crying in his ear and he's upset so he just elbowed the child,” the caller said.
Eyewitness Cindy Rosa told Inside Edition that the baby “had a horrible, horrible gash on his head. He had blood all over his face. His leg was broken.”
Sheriff's deputies in the Denver area say the accused dad admitted: "I was trying to kill my son."
“Being a father was a big responsibility and he did not think he was man enough to raise a child,” the deputies report also stated.
He has been charged with attempted first-degree murder.
It's a miracle that Isaiah survived.
Read: Mom Drowns Holding Son Above Water After He Fell in Lake: 'She Was An Amazing Mother'
The child's mother, Nancy Lopez, told Inside Edition: “It has been really tough on him and not be able to go play and do regular things that 2-year-olds do.”
She says the baby’s father needs mental help and “should stay in jail for the rest of his life.”
She has started a GoFundMe page and raised more than $30,000 to pay for medical and other expenses.
Watch: Toddler Found Drunk With Passed Out Underage Dad, Cops Say