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.
"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.