The father of a toddler who died inside a parked car at a Maryland naval base has been charged with involuntary manslaughter.

The 17-month-old boy was found unresponsive in a car parked at Naval Air Station (NAS) Patuxent River in Maryland around 3:25 p.m. Wednesday, according to a news release.

First responders attempted CPR, but the little boy was pronounced dead at 4:15 p.m.

Authorities said the boy was in the car for about seven hours. The outside temperature reached about 85 degrees Wednesday, they said.

The toddler's father, John MacDonald Junek, was in federal court in Greenbelt on Thursday in connection with the case.

Junek, who works on the base, left the little boy in the car, said an NCIS spokesperson.

According to charging documents, Junek, 40, told authorities that on Wednesday he took his 4-year-old son to preschool and then was supposed to bring his 17-month old to the Child Development Center on the base.

Instead, Junek said that when he entered the base, he drove directly to his office, leaving the toddler in a rear-facing car seat when he parked at 8:50 a.m.

Junek told authorities he got a call from his wife at about 3:20 p.m., asking if he had their son's car seat with him. He said he wasn't sure at first, and then realized he might not have dropped off the boy at the child care center.

He went to the car and found the boy still in his car seat. He called 911 and then tried to perform CPR on the boy until first responders arrived.

Junek also told authorities that around 1 p.m. that day, he drove to a meeting, but was in a hurry and didn't notice his toddler in the car.

According to the charging documents, Junek told authorities that it was very hot inside his car at midday, and he opened the windows and turned on the air conditioning as he drove to the meeting. Around 2 p.m., he drove back to his office, where he again parked and left the car with the windows rolled up, according to the documents.

Junek faces eight years in prison if convicted.