SAN FRANCISCO (KGO) -- People in one San Francisco neighborhood are coming forward after a senior citizen was brazenly punched in the head from behind in broad daylight.
72-year old Chi-Kwan Yen was out window shopping on Wednesday when the unexpected happened.
"All of a sudden I felt a pop in the back of my head."
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Chi-Kwan is a former West Portal resident now living in Palo Alto. He was back in his old neighborhood for an optometrist appointment last Wednesday when out of the blue a man, punches him in the head from behind.
"I have heart disease and I had an angioplasty less than a year ago. I'm still on blood thinners, so I thought, shoot, this might cause some bleeding in my brain. That's what I was really worried about.
Surveillance video used in the police investigation shows Chi-Kwan quickly jump back up.
"I exercise a lot and do some tai chi and martial arts," said Chi-Kwan.
Thankfully, he only suffered only a bump on the head and sore knees.
"I was lucky this time, but maybe next time, maybe I won't be so lucky."
After sharing video of the incident on social media, West Portal residents reached out to me to say they too knew someone who had been victims of unprovoked attacks in a similar fashion.
One of those people is Lynda Porter. Her 14-year old daughter Lily was out for a walk with her friend days earlier from Chi-Kwan's attack when she was punched and knocked to the ground.
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"There was no way to prevent it was random, senseless act of violence. She was psychologically distraught obviously," says Lynda.
While SFPD could not confirm a link between the attacks both have a similar M.O. It prompted Chi-Kwan to take action.
When asking why is important for you to come forward, Chi-Kwan answered thoughtfully and with passion.
"Asians need to stand up. Initially, I thought forget it I won't report it. Then I thought about it. We have to stand up to be counted. Otherwise, this will continue to happen. It might happen to me again."
Police say both investigations are ongoing.