Authorities say three New Jersey teenagers were playing a violent game called "knockout" when they beat a homeless man to death on a Hoboken street this month.

Two 13-year-olds and a 14-year-old were charged Friday as juveniles in the murder of 46-year-old Ralph Eric Santiago. He was found Sept. 10 with his neck broken and his head wedged between iron fence posts.

Hudson County Prosecutor's Office spokesman Gene Rubino said Monday that his office believes the teens were playing a game where the object is to see if they can knock out a stranger with one punch.

Rubino says his office has never seen a case this extreme. He says there is no decision yet on whether to try to have the teens tried as adults.

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