Police arrested 18-year-old Darriynn Brown in connection with the murder on Saturday evening and charged him with kidnapping and theft. Additional charges could be added depending on the investigation and forensic analysis results.
Now investigators are working to build a case against Mr Brown that included searching his home eight blocks away from the child’s house, which was where Cash was last seen alive.
At the home, investigators found “a tissue paper in a bathroom that had blood drops on it. A small pocket knife was also located and seized,” CBS 11 News reports.
Cash’s family confirmed that the young boy was the victim in the horrifying attack that has rocked the suburban neighbourhood in Dallas, Texas.
The boy was sleeping when the alleged kidnapper broke into the house and grabbed him around 5am local time on Saturday morning, his mother revealed.
An arrest affidavit said the incident was recorded on a video baby monitor in the bedroom, and it showed an intruder carrying the sleeping child out of his bed.
Police said the boy suffered from wounds made by an “edged weapon” in a “violent death” on Saturday morning. Cash’s body was found shoeless and partially clothed in the Mountain Creek neighbourhood by a jogger around 6:45am, just hours after he was taken from his home.
The mom told a local news organisation that she has no idea why the alleged kidnapper targeted her son and said she did not believe that the alleged killer knew her child.
But Mr Brown’s mom said the teenage suspect had mental health issues, and she did not think he was capable of committing a violent act.
“I think that four-year-old boy was killed at them [sic] people’s home and I believe someone had transportation, like a car or truck, and transported his body to the body site,” she told CBS 11 News.
Mr Brown was being held at the Dallas County Jail with a $750,000 bond.
Residents have created a memorial for Cash in the Dallas neighbourhood where his body was found over the weekend.