A Florida man has been accused of leaving his young son in a hot car for hours while he went to the barbers and had drinks at a bar — which he went back to that night after his son died.

Scott Allen Gardner, 33, was arrested on charges of aggravated manslaughter of a child and child neglect causing great bodily harm, the Volusia County Sheriff’s Office said. He is being held at the Volusia County jail without bond.

“This father is a human piece of garbage, and he’s a lying sack of s***,” Sheriff Michael Chitwood said.

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“He’s actually where he belongs to be, behind bars ... there’s no reason for this little boy to be dead.”

Authorities said Gardner’s 18-month-old son, Sebastian, was left in a truck for more than three hours on June 6 when it was about 32C outside.

The windows were slightly down and a small fan was on but that didn’t help, authorities said.

The child’s mother lives in another county, the sheriff’s office said.

Authorities said Gardner arrived at Classic Cuts about 11.30am and left Sebastian in the car while he got a haircut.

About noon, he went across the street to Hanky Panky’s Lounge where, authorities said, he drank beer and had shots for nearly three hours.

He left the bar about 2.40pm, drove a short distance to his mother’s home and called emergency services on 911, the sheriff’s office said.

Chitwood said when police arrived, the child was dead.

The hospital said the boy’s temperature was over 42C, Chitwood said. Hospital staff members believe the car got up to 44C.

Authorities believe the child was dead for about two hours before Gardner called 911.

In body camera video released by the department, Gardner is seen begging an officer to help his son.

According to Chitwood, later that night Gardner picked up his mother and they went back to Hanky Panky’s for drinks. Authorities do not believe Gardner’s mother was aware of what happened.

Chitwood ripped into Gardner.

“I don’t think there’s a penalty on this Earth that could ever fit for the crime that was committed here,” he said.

“It absolutely shocks the conscience.”