Potts said Bloomington police have had three prior contacts with Aranda in 2015 - two of which were connected to incidents at Mall of America.
Bloomington Police Chief Jeff Potts said at a midday Saturday news conference that the 24-year-old male suspect has been cooperative with investigators and remains in custody at the Hennepin County Jail.
"'She was screaming 'Everyone pray, everyone pray. Oh my God, my baby, someone threw him over the edge,"' Brian Johnson told WCCO.
The Chicago Tribune reports that Emmanuel Deshawn Aranda, 24, of Minneapolis, has been arrested on a suspicion of attempted homicide charge after witnesses to the attack identified the man. Aranda is supposedly banned from the mall, but somehow entered and randomly attacked the innocent boy.
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Potts said some of Aranda's past cases were handled through a mental health court, but would not comment further on the man's mental health status at the time of Friday's incident.
Emergency services rushed to the child who was lying in a pool of blood. A GoFundMe page has been set up to help the family.
On Friday, the boy "was enjoying a day at the Mall of America with his mom and friend ... when a stranger maliciously grabbed him and threw him over the third-floor balcony for no apparent reason".
He asked the public to keep the boy's family and first responders in their thoughts and prayers. "The child has been transported to the hospital and has been receiving care". Police credited a concerned bystander for chasing the suspect, and the Mall security for tracking him to the transportation station where he was apprehended.
"We think this is a very isolated incident", he said.
According to court records, the suspect has been previously barred from the Mall of America. Our immediate and only concern is for the wellbeing of the family and the child, as well as for any individuals who may have witnessed the incident. He had also swept his hand across a display table at the beauty store Bare Minerals, breaking lip gloss containers and shot glasses, police said.