ATLANTA (AP) — A Georgia man accused of leaving his 22-month-old son in an SUV on a hot day returned at lunchtime to put something in the vehicle, where the child was strapped into a seat in the back, according to an arrest warrant filed Tuesday.

The warrant also downgrades one charge against 33-year-old Justin Ross Harris, from first-degree child cruelty to second-degree child cruelty. First-degree cruelty to children requires a person to "maliciously" cause "cruel or excessive physical or mental pain," while second-degree cruelty to children is caused by "criminal negligence" under Georgia law.

The toddler died, and Harris also faces a murder charge. He was being held without bond.

Harris put the toddler in a rear-facing car seat in the center of the back seat of his Hyundai Tucson after eating at a Chick-fil-A restaurant the morning of July 18, the new warrant says. He then drove about 10 miles to work and left the child strapped into the car seat when he went inside, the warrant says.

At lunchtime, Harris returned to the vehicle and opened the driver's side door to place an object inside and went back inside his workplace, the warrant says. It does not explain how the officer knows that.

Around 4:15 p.m., Harris left work and, soon after, pulled over at a shopping center and asked for help with his child, the warrant says. The child was left in the vehicle for about seven hours, the warrant says. The temperature that day was 88 degrees at 5:16 p.m., according to the first warrant in the case, filed the day after the child died.

Harris has told police he was supposed to drive his son to daycare but drove straight to work without remembering the boy was strapped in his seat until the ride home.