Kentucky State police said Joseph Brock, who would have turned 2 this month, was found stuffed inside the machine after the fire Saturday, according to WKYT-TV.
The boy's father, Vaughn Brock, reportedly ran from the home after the fire started and wasn't seen for days, WKYT reported, citing police.
He was finally arrested Wednesday, after a three-day search.
Brock initially told police he fell asleep on the couch after smoking a joint and that he woke up to smoke and fire. He said he didn’t know how the toddler ended up in the washing machine.
He later admitted to detectives that the boy was acting up, before requesting an attorney and ending the questioning, the station reported.
Brock is now jailed on a $500,000 bond.