SAN FRANCISCO (CBS) — A video of a knife-wielding driver chasing a group of young men around Union Square on Pride weekend has San Francisco authorities scratching their heads.

The incident happened on Sunday, the same day as the SF Pride Parade.

The man looks to be Asian, and despite the fact that he is holding a sharp object, a group of pedestrians taunt him, throw objects at him, and in one case, actually hit him. The man seems undaunted, and chases them around, finally retreating to his pickup truck.

According to police, there were 15 felony arrests, 11 misdemeanor arrests and dozens of arrests for public intoxication on Sunday, but no report was ever filed related to this incident.