For South Korean international student Annie An, a tutoring session at a Walnut Creek Starbucks last weekend turned into a nightmare.

An, who’s attending a community college in the East Bay, was going over an essay with her tutor, South Korea native and UC Berkeley student Sean Lee, on Sunday, when a patron overheard the two speaking in Korean, KRON reports.

“This is America. Use English only,” said the unnamed woman, who was sitting nearby using a laptop, according to An.

An began filming the confrontation as Starbucks employees asked the woman to leave.

“I hate it,” the woman says on the video. “If you can sit and be quiet, fine, but I don’t want to hear your language.”

“We have the freedom to use my own language,” An responds.

Starbucks employees continue to ask the woman to leave. “They’re welcome to be here, they’re doing nothing wrong. You’re the one that’s causing an issue,” an employee tells her.

“You’re gonna be in trouble when I get this letter out,” the woman responds. An employee points out that she’s just tapping numbers on the keyboard.

Another employee then tells her she needs to leave or they’ll call the police.

Three officers later escorted the woman out of the coffeehouse. An said the woman continued to complain about the use of Korean as she was forced to leave.

An’s video had been viewed by almost 500,000 people and been shared more than 4,500 times by Thursday morning.

“Some specific words she mentioned made me so mad,” An wrote in a Facebook post. “Especially ‘Korean,’ ‘disgusting,’ ‘be quiet and sit down,’ ‘English only’ and ‘immigrants.’ ”

“This is the most unexpected and unbelievable day for me this entire 2017,” An said, thanking Starbucks employees for coming to her assistance.

“In our day-to-day pursuits and responsibilities, it’s all too easy to forget that racism and anti-immigrant sentiments are a real thing in this country, even in the Bay Area that so often touts ‘diversity,’ ” Lee wrote in a separate Facebook post. “Hopefully, this leads to even more conversations and initiatives.”