According to the , his father told 911 operators that "there's no way he could have got out."
During the emergency call, he continued: "I've checked the whole house, the basement, everything. I've been yelling his name."
Six minutes later screaming can be heard, before an unidentified woman said: "We've found him in a pond of the next door neighbor's house, and we're trying to do CPR right now.
"We're getting some water out, but I don't know," the voice said, before trailing off.
The father said that he went to get his son socks from another room, before returning to find him missing.
He said: "I didn't think he'd be able to unlock the door and go outside without me knowing."
Police were called to the scene at around 3.45 p.m.
Paramedics and firefighters also tried to resuscitate the boy when they arrived, before pronouncing the toddler dead at the scene at 4.28 p.m.
Evansville Police Department Detective Sergeant Peter DeYoung told the outlet: "At this time, we have to do the same process, regardless, and make sure we contact and talk to as many people as possible to find out exactly what happened."
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