It happened around 4 pm Tuesday afternoon near the Abby and Divisadero stop.
Officers responded within minutes, arresting a man and a woman.
Investigators say the suspects did not know the victim and that the incident does not appear to be gang-related, racially motivated or involve anyone in the unhoused community.
"It was an argument over the seat, over who is going to be on the seat," says Fresno Police Sergeant Diana Trueba Vega. "The suspect told the victim they were sitting in the seat and asked him to move. The victim refused, and that's when the disturbance ensued."
The victim was rushed to the hospital in critical but stable condition. A second passenger suffered a minor cut to the hand.
We're told the driver quickly stopped the bus and safely evacuated at least three bystanders.
The incident put a spotlight on bus security.
A frequent bus rider said that she wishes fellow passengers got inspected before they entered the bus.
"I feel like that's scary," says Krisshay Madden. "There should be more rules, like getting your pockets checked or whatever, to get on the bus."
Luis Montoya, president of the union representing city bus drivers, is calling for increased safety measures, including more training for drivers.
The man who was arrested is facing a felony charge of assault with a deadly weapon, while the woman was booked on a felony accessory charge.
Montoya is thankful the victim survived.
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