The San Francisco Police Department is seeking a man on suspicion of assault with a deadly weapon today, after he struck a victim with a baseball bat.

Police say that the attack occurred some time between 9 and 10 p.m. on Sunday night on the 2700 block of 21st Street, which is between Bryant and York Streets.

According to the SFPD, the suspect approached a 44-year-old man from behind, and hit him on the back of the head with the bat. The suspect then fled in an "unknown direction," police say.

The victim was transported to San Francisco General Hospital for his injuries, which police say are not life-threatening. The suspect, who police only say is "male," remains at large as of Tuesday morning.

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