An MBTA bus driver told a Dedham man he had to pay. That’s when the racist rant began, police say.

Daniel Moreno.

A Dedham man allegedly began shouting racial epithets and threats — and eventually threw a rock  — at an MBTA bus driver in Mattapan after he was asked to pay his fare last Saturday.

Daniel Moreno, 21, was arrested on Wednesday and charged with assault and battery with a dangerous weapon following an investigation into the incident, according to MBTA Transit Police.

Moreno reportedly tried to get on a Route 30 bus at Mattapan station without paying. The bus driver then told him to pay or he couldn’t get on.

That’s when Moreno’s racist diatribe began, police said.

Then, when the driver attempted to exit the station onto Blue Hill Avenue, Moreno allegedly threw a rock that hit the driver in the torso. He was also shouting profanities, according to police.

The bus driver was not seriously injured.