The fight was caught on camera and now the MTA is looking into the video.
It began with some very aggressive and offensive behavior towards an elderly man and woman on the bus.
A man lunges at the couple. People we showed the video to were cringing.
"Oh my God, did he attack him?," said Bushwick passenger Michelle Peace.
But then, we showed them what happened next. The elderly man, with a cane, felt he had to stand up to defend the woman next to him.
Next, an unexpected display of street justice. Almost everyone else on the front of the bus had his back, slugging the suspect. And people who watched the video couldn't agree more.
"Good, they're not gonna take it anymore. That's New York, I like New York. We come together when we need to. We might be all different nationalities, all different cultures, but if we feel somebody is wronged in our presence we come together to help them out," said Peace.
"What would you do?", we asked Janet Forde of Flatbush. "Same thing," she said. "Jump on the guy?" "Yes why not, hit him with my cane!," she said.
Because those who ride often know there are moments where passengers need to step up, and don't.
"What's the worst thing you've seen?" we asked Bedford-Stuyvesant passenger Gil Gainey. "Similar to that," he said, adding that people didn't do anything to help.
"So this is unusual?" "This is unusual," he said.
If you know about what happened on that bus, or know anything about the suspect, police and the MTA want to hear from you.
If you know the elderly man with the cane, we'd like to hear from you. Send a tweet to @staceysager7.