An apparently off-duty Muni employee was captured on video yesterday morning hurling racial slurs at a woman following a disagreement involving a parking spot. Posted to Facebook, the video has garnered significant amounts of attention, and, reports the Chronicle, resulted in an SFMTA investigation into the driver's actions.

"Racist, ignorant, Muni bus driver gets mad at me for taking an open parking spot," wrote Mayra Villarreal, the woman filming the encounter. "I am reporting this to the SFMTA HR department and posting it on KRON 4 news website. People like this make me sick!"

Throughout the video, Villarreal remains extremely calm — referring to the man as "sir" even has he repeatedly disparages her.

“I was waiting," the man says, apparently referring to a parking spot. "You’re just a n*****, that’s OK. That’s fine.”

“I’m a what?” Villarreal replies.

“You’re a n*****.”

“I’m not even black.”

It doesn’t matter,” the man, still wearing his Muni uniform, responds. “Your mentality’s a n*****.”

SFMTA spokesman Paul Rose confirmed to KRON 4 that the man in the video is in fact an employee with the agency. “We just identified him and are taking immediate and corrective action,” explained Rose. Rose declined to publicly identify the man.

While both the Chronicle and ABC 7 say the man has been placed on leave during the course of the investigation, KRON 4 reports that an unnamed spokesperson with SFMTA told them the employee is not in fact on leave at this time.

Villarreal is a Business Major at San Francisco State University, and was on her way to work at the time of the encounter. “I just took out my video because I was scared," she told KRON 4, "just for safety reasons."

Update: According to CBS 5, San Francisco Mayor Ed Lee yesterday joined with SFMTA officials in calling for the firing of the Muni operator caught on video using racial slurs. "This ugly behavior will never be tolerated," Lee said in a statement. "I applaud the SFMTA for taking swift action after this video came to light and seeking termination for this individual.”

It seems at least one SFMTA official is in agreement with the mayor, with The Examiner reporting on a letter addressed to all staff from John Haley, SFMTA's Director of Transit. "There is simply no acceptable excuse or mitigating circumstances to justify [the operator's] actions and we have moved to terminate his employment at the agency," wrote Haley.

Related: Etiquette Week: How To Ride A Muni Bus