SAN FRANCISCO (CBS SF/BCN) — A suspect remained at large early Thursday and his victim hospitalized with critical injuries suffered in a carjacking near San Francisco’s Union Square.

San Francisco police said the incident took place in the 200 block of Geary Street around 1:10 a.m. Wednesday.

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Officers responded to 911 call of an assault and learned that a suspect had jumped into a vehicle after the victim had left it running.

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As the suspect began to drive off, the victim jumped into the moving vehicle but fell out. The victim was taken to a hospital with critical injuries.

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Police have not released further information, including detailed descriptions of neither the suspect nor the vehicle.