He said the child was lying 'motionless, he was in a pool of blood'.
Potts confirmed that there is video that occurred during the incident, but said it will not be released until the investigation is complete.
Potts said on Saturday there were "a lot of witnesses that were helpful" in the incident Friday.
The boy was initially reported as not breathing, but is being treated at a hospital but there was no immediate word on his condition.
"This was a tough one", Bloomington Police Chief Jeff Potts said in a press conference on Saturday afternoon, describing the scene upon his arrival at the mall on Friday as "gutwrenching".
"Immediately, my thoughts were: how can something like this happen?"
He's now at the Bloomington Police Department, Potts said, and authorities don't believe there is any further threat to the public.
Police received an initial report at 10:17am saying a child had fallen from the third level of the mall, but witnesses reported the child was pushed or thrown by a man, Potts said.
"This was a senseless act and words can not truly express our profound shock and sadness, ' the Mall of America said in a statement on Friday".
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Aranda has been banished from the mall in past years, though authorities said the trespassing holds had expired by Friday's incident.
Police say both the victim and Aranda live in the Twin Cities. Aranda also was accused of walking into a mall store and sweeping his hand across a display table, breaking glasses.
Aranda was banned from the mall for one year. He is expected to be charged with attempted homicide. Aranda had smashed five computers and keyboards "beyond repair" after he read something on Facebook that infuriated him, the man told authorities. Court records show he was charged in two previous incidents at the mall and at one point had a trespass notice banning him from the mall.
He was arrested on six misdemeanour charges. He was ordered to get a mental health evaluation as part of his sentence in that case.
Potts said the department will focus on preparing its submission for formal charges at the Hennepin County Attorney's office and anticipates charges will be filed on Monday.
Brian Johnson told WCCO-TV the woman was screaming, "Everybody pray, everybody pray".
In the meantime, please send up a prayer for the little boy. "Why would you single out a kid and ruin a family's life like this?"