A seemingly unprovoked stabbing Thursday afternoon in San Francisco's Chinatown left one male victim with life-threatening injuries. Police have arrested a suspect.

The attack took place at the corner of Stockton and Sacramento streets in Chinatown around 1:13 pm Thursday. The SFPD responded to the scene and found the male victim suffering from a stab wound to the back.

KRON4 subsequently obtained surveillance video that shows the attacker, dressed in a black hoodie and carrying a shopping bag, approach the victim who was waiting at the intersection to cross the street. The suspect then thrusts a knife forcefully into the victim's lower back, and continues walking into the intersection.

The victim can be seen grabbing his back, and then falling to his knees in apparent pain.

Passersby seem to ignore the victim, but one person is seen stopping to call for help on their cellphone.

The victim was said to be suffering from a life-threatening injury, and was hospitalized. His current condition is not known.

Police quickly located a suspect matching the description of the stabber on the 600 block of Powell Street, and he was reportedly detained without incident. As KRON4 notes, no pending charges have been publicized.

This seemingly unprovoked attack took place several hours before an altercation in the Tenderloin that left two members of Mayor Daniel Lurie's security detail injured.

Top image: Photo by Justin Sullivan/Getty Images