The suspect in thechilling, seemingly unprovoked daylight street stabbingcaught on camera in San Francisco may have known the victim he crept up behind and viciously stabbed in the back.

The manager of a business near the scene of the shocking attack said police told her and other workers that the victim and suspect knew each other, theSan Francisco Chronicle reported.

The suspect, who police described as Asian male in his 30s, was arrested and held on attempted murder charges,KTVU reported. He needed help from a Chinese language interpreter during his police interview.

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Video of the brazen stabbing showed the suspect casually walk from behind the victim before before plunging and knife in his back and running off.

The victim recoiled and eventually dropped to the ground while bystanders made their way by him without rendering aid.

He was transported to the hospital with life-threatening injuries but is expected to survive, KTVU reported.

The suspect, who has not been identified, was detained near the 600 block of Powell Street about 10 minutes after the incident.

The suspect’s motivation for the attack remains unclear. Cops told KTVU that the victim and assailant “appear to be local to the community.”

Source: California Post – Breaking California News, Photos & Videos