PALM HARBOR, Fla.  — A Tampa-area father has been charged with aggravated manslaughter in the death of his 23-month-old son, who was left in a pickup truck for eight hours, authorities said.

Troy Whitaker, 41, of Palm Harbor, placed his son Lawson and 5-year-old daughter in his pickup truck the morning of Sept. 9 and took the girl to school, according to a statement from the Pinellas County Sheriff’s Office.

Whitaker then drove home without taking Lawson to day care and left him unattended inside the truck until about 3:30 p.m., when he drove to a nearby grocery store, and he didn’t notice Lawson was still in the back seat of the truck until an hour later when he got home and began unloading groceries, detectives said.

According to the sheriff’s office, Whitaker is a Hillsborough County Fire Rescue firefighter, and he attempted to revive Lawson after calling 911.

Lawson was pronounced dead at a hospital.

Pinellas County Sheriff Bob Gualtieri told the Tampa Bay Times that Lawson’s body temperature had reached 108 degrees.

Whitaker told detectives that he thought he had dropped Lawson off at day care in the morning, according to the Sheriff’s office.

Whitaker had driven home to study for an exam at the fire department, Gualtieri said.

“You’ve got to be responsible for your kids. You can’t leave them in a hot car and let their temperature get up to 108 degrees,” Gualtieri said. “He did this with negligence . and under Florida law, that is child abuse. He has got to be responsible for his actions.”

Aaron Begay told the newspaper that he was mowing his lawn across the street from Whitaker’s home when he heard the man screaming.

“I can’t believe it, I can’t believe it, I can’t believe it,” Begay said he heard Whitaker crying.

Begay said Lawson’s body was limp as his father pulled him from the truck and began CPR. Whitaker had called 911, but Begay said he had to pick up the phone because the father was inconsolable.

Whitaker was released from the Pinellas County jail on $50,000 bond. Jail records didn’t show whether Whitaker had an attorney.

A fire rescue spokesman, Corey Dierdorff, said that the agency would not comment.