The youth group was driving down the interstate on Sunday when they spotted the auto seat, thinking it may be a doll at first, according to KFOR.
According to the Facebook post, a church group was on their way home, when they noticed the auto seat on the side of the busy highway.
He said about 15 members of the 120-congregant church were travelling back to Ada, about 135 kilometres southeast of Oklahoma City, when the youth leader saw the auto seat.
According to police, the baby was not on the side of the road for more than 30 minutes.
The youth group from Abba's House Worship Center was on their way home to Ada from a field trip to Frontier City on Saturday.
Several other drivers pulled over, startled by the sight of the 1-month-old abandoned near a freeway, facing oncoming traffic.
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They described his demeanor as "professional" and said they had "no reason to believe" that he would harm himself, Aaron said. Nashville police did not immediately comment on several weird posts on the suspect's page in the hours before the shooting .
"More than likely, they're not going to file charges", said Capt. A Social Security card was also found with the baby.
A baby was found over the weekend sitting in a vehicle seat only about 10 feet from fast-moving cars on Interstate 40, and police are now looking for answers.
Authorities tracked down the baby's mother, but have not revealed a motive. The baby was reported to be "completely healthy", according to a police report.
Both infant and mother were taken to a local hospital and given a clean bill of health. Authorities are investigating why and how the baby was left by the side of the northeast Oklahoma City highway.
"We don't know why she did what she did ... but people do the strangest things sometimes", Knight said.