Is the so-called "knockout game" a real thing?

Police in several U.S. cities are investigating a string of attacks that may be part of a disturbing trend in which the attackers, mainly in their teens, target unassuming victims seemingly at random, knocking them unconscious — and, in at least one case, killing them — with a single punch.

In Hoboken, N.J., in early September, police say a 46-year-old homeless man was attacked, suffering a seizure and falling into a nearby wrought iron fence, which fatally punctured him. The juvenile assailants, who struck the man from behind, were later arrested and charged in connection with the killing.

In New Haven, Conn., police say they are investigating as many as six "knockout" incidents that have occurred within the last month.

In Brooklyn, N.Y., on Friday, police say a 24-year-old Jewish man wearing a yarmulke was assaulted by a 28-year-old Trinidadian man who had been talking about knockout games before the incident. He was charged with a hate crime. The Jewish man was not seriously injured.

The NYPD said there have been at least seven "knockout" incidents in recent months, leading Police Commissioner Ray Kelly to order extra officers in Crown Heights, a Brooklyn neighborhood where some of the alleged "knockout" attacks have occurred.

Last week, Republican New York State Assemblyman Jim Tedisco said he was drafting a "Knockout Assault Deterrent Act," legislation calling for juveniles charged with the random assaults to be tried as adults.

“What’s shameful is not only that these punks are knocking out innocent people, but they’re trying to rack up knockouts to impress their friends," Tedisco said, calling the game "barbaric." "What's even more dangerous is they’re trying to rack up the most number of knockouts because it becomes a status symbol in the gang."

But some say drawing attention to the "knockout" trend isn't necessarily a good thing.

"When you highlight an incident or a type of criminal activity, some people will simply try to copy it," Kelly said Friday. "It's a phenomenon we've seen before."

Knockout incidents have been reported in other major cities, including Philadelphia, Washington, St. Louis and Chicago.

"That's America," Chuck Williams, a professor and youth violence expert at Drexel University, told CNN. "America loves violence and so do our kids. We market violence to our children and we wonder why they're violent. It's because we are."

Some of the alleged attackers have boasted about their knockouts on social media, helping fuel the trend.

But is the "knockout game" an epidemic?

No yet, Will Marling, the executive director of the National Organization for Victim Assistance, told USA Today. "But it could be the start of one. As experience shows, other kids will see this is an easy thing to do, and then it becomes group think."

Others say it's an isolated trend, but not a new one.

“There is no evidence supporting this as a huge, viral number of attacks," Mike Males, senior researcher for the Center on Juvenile and Criminal Justice, told the Christian Science Monitor. "I’ve heard of incidents of this so-called 'knockout game' dating back to 1996. It’s not new. What is important to realize is this tiny 'knockout' pattern is part of a stronger pattern of random violence against strangers in this country."

“If there ever was an urban myth, this was it,” Jersey City police spokesman Bob McHugh, told the New York Times.

Even Kelly isn't sure the problem is widespread.

“We’re trying to determine whether or not this is a real phenomenon,” Kelly said on Friday. “I mean, yes, something like this can happen. But we would like to have people come forward and give us any information they have.”

In Syracuse, N.Y., police say two fatal attacks connected to the knockout game this year have sparked legitimate concern.

“I think it’s very real,” Sgt. Tom Connellan said. “As opposed to a motive for assault, be it anger or robbery, this is strictly for a game.”

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