A surveillance video that's been blurred at police request still shows a disturbing daytime attack in San Francisco, as a man runs up from behind a woman to bash her, then comes back to hit her again as she cries for help.

The date stamp on the surveillance video says the incident happened on August 10 at around 8 p.m.. According to KRON 4, it occurred on Sweeney Street near San Bruno Avenue.

In the video, which is taken from footage from two area cameras, we see the man walking like any other normal human being. But as he approaches the woman, he breaks into a run and smacks her on the back of the head then punches her repeatedly, knocking her to the pavement. When she appears to object to the attack, he returns and strikes her again.

"This doesn’t appear to be an attempted robbery," KRON 4 reports, "since he didn’t take her handbag or the shopping bag she was carrying."

The faces of both the suspect and the victim have been blurred out at the request of the San Francisco Police Department, citing their ongoing investigation.

The SFPD "remains tight-lipped about the incident," NBC Bay Area reports, only confirming that the victim in the attack is Asian. KRON says she's 31, and was treated at California Pacific Medical Center for injuries sustained in the attack.

Police do believe that the attack was unprovoked, KRON 4 reports, but refused to comment on if the suspect is believed to have attacked other victims.

“I’ve never seen something that someone would just come out of nowhere and hit a woman and she falls to the ground and then still comes back,” a neighbor told KRON 4.

“This is like it wasn’t enough, so I’m horrified. And I normally walk with my grandson. And I walk with my parents who are elderly. And I walk with my kids. Now you got to start thinking, ‘Gosh I got to watch my back, check the backseat (if someone) was walking behind you.”

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