Police across the country have seen an alarming rise in a dangerous gamed called ‘Knockout' in which teenagers attack random people on the street, attempting to knock them unconscious with a single punch.
It's happened in half a dozen cities and authorities said the number of cases are on the rise.
In Pennsylvania, school teacher Jim Addlespurger became a victim while walking home.
"I was hit with one punch,” Addlespurger said. “I’m fortunate that I’m alive to tell you about it."
Other knock out cases have been reported in San Diego, St. Louis and Chicago.
"It appears these are just random acts of violence,” said former FBI profiler Clint Van Zandt. “It’s just simply youth making the decision that they are going to punch somebody out, sometimes with as little as a five dollar bet between them."
With many YouTube video showing up online police are concerned about copy cat cases.