Tionna Smalls does not remember when tensions between black residents and Korean-American merchants rocked her Brooklyn neighborhood decades ago. But when she saw a video of Asian nail salon workers attacking African-American customers last week, she said she knew exactly what she was seeing.

“I’m tired of the disrespect in the black community,” said Ms. Smalls, 33, a former star of the VH1 reality show “What Chilli Wants.”

The video of the melee went viral. Ms. Smalls took to Twitter to call for protests. People from around the country flooded the website Yelp to denounce the salon, calling its workers racist, often in incendiary language.

Within hours of Ms. Smalls’s tweet, an angry crowd of several dozen people gathered outside the business and picketed nearby stores.