Justin Ross Harris has been charged with murder after he left his son in his SUV all day while he went to work. Courtesy: Fox News

COOPER Harris, just 22 months old, was meant to be dropped off by his father at daycare.

Instead his father Justin Ross Harris, who was said to adore his only child, drove to work as normal.

He parked his blue Hyundai Tucson, with Cooper strapped in a baby seat, on a day when temperatures hit 32C. Inside the car the temperature would rise to close to 60C within hours.

Justin Ross Harris, 33, left his work at Home Depot’s headquarters in Marietta, Cobb County, Georgia, and went back to his vehicle and began to drive home.

It was only then that he looked behind him and saw his son in the baby seat. He pulled into a shopping centre car park.

Police said Harris had to be physically restrained once it became clear his child was gone.

“He hopped out of his car. I didn’t know what he was doing at the time,” co-worker Dale Hamilton told WGCL-TV.

“But, he eventually pulled the child out of the car seat. I guess he was trying to un-restrain him. He pulled him out of the car seat, laid him on the ground and was trying to resuscitate him.

“He was constantly saying, ‘What have I done, what have I done.’”

Cooper had allegedly been in his dad’s car for about seven hours.

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“It is tough, I am not sure how someone could forget they have a child in the back seat,” Hamilton said.

Cobb County Police, who saw the commotion and intervened, said Harris had to be physically restrained once it became clear his child was dead.

Cobb County District Attorney Vic Reynolds told The Atlanta Journal-Constitution the investigation is “far, far from over.”

“I don’t know where this investigation will ultimately lead,” he said in a phone interview with AM 750 and 95.5 FM News/Talk WSB.

“When a suspect is charged with a felony — such as cruelty to children in the first degree — which results in the loss of life, a murder charge is appropriate,” Reynolds said

“It’s just a terrible, God-awful situation ... I can’t imagine, I can’t fathom what any parent would be going through at this stage. It’s the type of case that affects the community.”

In addition to murder, Harris is charged with cruelty to children in the first degree, according to his arrest warrant.

He was silent and showed no outward emotions when he appeared before a Cobb County magistrate in which the judge told Harris’ attorney he could not set bond because of the seriousness of the charges.

Harris’ attorney Mattox Kilgore confirmed he and client understood he was not eligible for bond.

Harris will remain in jail until his next court appearance, scheduled for July 15.

Harris, his wife Leanna and toddler Cooper were renting a condo but hoped to buy a home, Landlord Joe Sainti, said Harris and his wife are “very, very nice” people who were in love with their baby.

“Everything was going right for this couple,” Saini said. “They wanted to buy a house so they could have some space for their child to run around the backyard.”