Authorities say the incident happened Saturday afternoon at Again Thrift & More, operated by the Minnesota Valley Action Council.
A GoFundMe page has been established to help the family with funeral expenses.
Police Cmdr. Daniel Schisel says the boy apparently got the hooded sweatshirt he was wearing caught on a hanger attached to a wall, and was accidentally hanged. He was pronounced dead at the Mankato hospital. He calls the death "a tragic accident" and says no charges are being pursued. Police interviewed the boy's guardians and reviewed security footage from the store.
The boy has been identified as Ryu S. Pena. The page describes Pena as "a sweet boy, with a gorgeous smile, an a unique little personality, his best friend was his older sister Glory". "And he just became a big brother 4 months ago to Rolando Jr., whom he loved so much".