WATCH: White men go berserk after inserting themselves into dog park dispute between Black families

A man shouted racist abuse and another coughed on a Black woman after inserting themselves into an encounter at a California dog park.

Nicole Terrell and her 6-year-old daughter had taken their 6-month-old emotional support animal Thursday afternoon to Highlands Ranch Park, where another dog with a different Black family attacked their dog, reported KGO-TV.

"They apologized and they said they were leaving, and [said], 'I'm so sorry,'" Terrell said.

But then a man who wasn't involved jumped into the interaction claiming to be a federal agent and called 911 after one of the family members poured water on him, and then a second man approached and coughed in Terrell's face.

"Out of nowhere a man just started saying vulgar racist slurs toward the African-American family, which prompted me to start recording," Terrell said.

Terrell said Pittsburg police treated her like a suspect when they arrived, and she contacted the City Council to complain.

Pittsburg police insisted they were taking the investigation "very seriously" before handing it over to the district attorney for possible charges, and an independent review was also underway into the responding officer's conduct at the scene.

KGO contacted the man who called 911 during the incident, and he claims he was trying to protect Terrell's dog but felt threatened by the Black family.

"I regret [using the racial slur] the moment it came out of my mouth," said the man, who asked not to use his name due to safety concerns. "I apologize for my behavior, you know? I'm normally a pretty well-controlled guy, I don't think I've ever said anything like that in my life."