A Muni rider got the fright of her life Monday, when a fellow passenger set her hair on fire.

According to the San Francisco Police Department, the 50-year-old female victim was riding a Muni bus near Eighth and Market Streets at 8 p.m. Monday when the incident occurred.

Police say that a 37-year-old man who was seated behind the victim pulled out a lighter and set the victim's hair on fire, then fled the scene. He was later located, police say, and was arrested on suspicion of aggravated assault.

A quick-thinking friend of the victim extinguished the blaze, police say. Other than the tonsorial indignity, the victim was not injured in the attack.

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