Rose McGowan told her Twitter followers that she witnessed a knockout game attack in LA. The "Charmed" actress chased down the attacker. In spite of Rose McGowan's account, police in Venice, Calif., say they will not be investigating the incident.

Rose McGowan says she witnessed a young man randomly punch an elderly man. McGowan attempted to chase the culprit but he got away. Venice police said they will not investigating the  knockout" game attack.

According to her Twitter feed, Rose McGowan saw a masked "evil guy" during a knockout game attack in L.A. on Thursday. McGowan says the man punched a 65-year-old man and run off.

Rose McGowan was walking around Venice, Calif., when "I just witnessed a 65 year old man get punched by an evil guy playing that goddamn knockout game. #criminal #heartbroken #whattheF?!"

The "knockout game" is a recent trend. Reports say teenagers randomly punch a stranger to see if they can knock them out with one punch. Authorities have reported at least seven knockout game attacks in New York, Illinois, Missouri, Washington and elsewhere.

The New York Times, NPR and other media outlets dismiss "knockout game" attacks that have been reported across the country as "overblown."  But McGowan tweeted that she saw an elderly man get attacked. She said she chased down the knockout game assailant but couldn't catch him.

On her Twitter account, McGowan said the attacker was wearing a mask and riding a skateboard. Rose says the victim was walking his dog. The dog tried to protect him, but couldn't fend off the attacker. McGowan said the victim was bleeding from the ear. Rose called for an ambulance.

Venice police detective Lt. Mark Day said that no investigation is underway in his squad but a different division within LAPD may be on the case. He said no victim has stepped forward.

Day said "We haven't located an incident. It was actually the media who alerted us to this, but we can't find anything. There's no investigation until somebody comes forward. We need to make contact with a victim."

LAPD Media Relations Section Officer Rosario Herrera said that "there is no victim, and there was no report taken."

Neither the attacker nor the victim has been identified.