2:48 PM PT -- The attacker, Cedric Charles Moore Jr., turned himself in Wednesday to the Scott County Sheriff's Office in Benton, Missouri. As we've reported ... he was already charged with felony assault in the second degree and felony child endangerment in the first degree due to the age of the victim and the violence of the act. His bond's been set at $50k cash only.

Sergeant Joey Hann with the Cape Girardeau PD said he "hopes that this arrest offers a sense of peace and security to the young victim and his family. Our department would also like to thank the large volume of information we received from the public on Cedric Moore. Your concern for decency and your tips on his whereabouts left this violent suspect with nowhere else to hide and helped to lead to his peaceful surrender."

It's impossible to make sense of the brutal, random act of violence against a 12-year-old dancing in the street, but humanity's shining through to help out the victim.

The tough kid's name is Ethan, and his mother, Stephanie Hagler, tells TMZ ... more than 400 people -- family, friends and strangers alike -- have raised more than $14,000 so far to cover his medical bills and more.

Waiting for your permission to load the Instagram Media.

ncG1vNJzZmivp6x7tbnZZ5qopV9nfXN8jmluaGhoZLqqv9KorKuhXZbAtK3UpatmaWJixrB5yqKbZpyRo7CqusZmqZqmlKS6bq3TrZico12bwq%2Bw0ZqgrJ2iYrWmuM9mmaKknKh8