A man kicked out of a Mission District business for smoking reacted most aggressively Thursday, attacking the man who told him to snuff his butt.

The dispute began at 4 p.m. Thursday, in a business on the 2900 block of 16th Street,which is between South Van Ness Avenue and Mission Street.

Police say that the suspect, a man in his 40s, was smoking inside the business, an act likely prohibited by San Francisco law.

A 24-year-old man told the smoker that, if he wanted to smoke, he must leave the business. As opposed to complying, the smoker punched the man and "causing injury," according to the San Francisco Police Department.

The blow was severe enough that the injured man was transported to an area hospital for treatment, police say. Meanwhile, the smoker fled in an "unknown direction" and remains at large as of Friday morning.

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