Minneapolis police spokesman John Elder tells the Star Tribune the boy somehow "slipped through the railings" of the balcony and fell unimpeded to the ground.
Police say it happened shortly after 10 p.m. Sunday.
The boy was taken to Hennepin County Medical Center, where police say he is in critical but stable condition. The child's identity hasn't been released.
Information from: Star Tribune, http://www.startribune.com
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