"He was yelling `f*** white people'."
Ms Chen said the man went to leave the shop and one of the young customers moved to close the door.
At this point, the man kicked and smashed the thick glass window at the bottom of the door.
Ms Chen, who has owned the student-favourite takeaway for 17 years, said the man had only started coming to the store this year.
She described a "horrible smell" of alcohol emanating from him.
"All the time, he's drinking."
There were no CCTV cameras in her store but she was confident footage of the man would have been captured by the University of Otago's cameras and she understood he lived nearby.
She was fearful the man would return and had been advised by police to take a photo if he again entered her shop.
"I'm really scared."
A police spokeswoman said they had received a report shortly after 3.30pm of wilful damage.
As of tonight he had not been arrested, she said.