Tião was a solitary male bottlenose dolphin that was first spotted in the town of São Sebastião in Brazil around 1994 and frequently allowed humans to interact with him, having a particular preference to interacting with female humans.
After several months, the animal moved north to a local beach, where he frequently got close to bathers and interacted with them.
Harassment of the dolphin started to take ever more serious forms, from people attempting to restrain the dolphin to have their picture taken with him, to trying to stick an ice cream cone in his blowhole and attempting to pour beer into his mouth.
When in December 1994 two male swimmers, Wilson Reis Pedroso and João Paulo Moreira, were harassing and possibly attempting to restrain Tião, in a beach of Caraguatatuba, the dolphin broke the ribs of Pedroso and killed Moreira, who was later found to be drunk.
Tião remained at the town for a few more months but finally left for good during the summer of that year, most likely having rejoined a pod, though some still speculate he may have been killed out of revenge.