A 22-year-old Sikh, studying at the prestigious Harvard Law School, was allegedly abused and harassed at a store near the campus by a man who mistook him for a Muslim.

Harmann Singh, a first year law student at the university, said he was shopping in a store in Cambridge, Massachusetts, while speaking on the phone with his mother, when a man walked in and said to the clerk behind the counter, “Oh look, there’s a (expletive) Muslim.”

“Over the weekend, I was confronted by a man who called me a ‘(expletive) Muslim’ and followed me around a store aggressively asking where I was from, and and no one in the store said a thing. I was on the phone with my mom the entire time, and we were both concerned for my safety as this man stood inches away from me,” Singh wrote about his experience in The Boston Globe.

“While deeply painful, what happened to me pales in comparison to the hate and violence many of my brothers and sisters have faced across the country,” he wrote.

According to Singh, the man started following him around the store, harassing him and asking him where he was from.

Singh, who is from Buffalo, New York, said he tried to ignore the man and continue his conversation with his mother, who was worried.

She could hear the man questioning Singh and told her son to leave the shop. Singh said the man followed him to the checkout counter.

“I told him, ‘Hey I’m actually from New York. I live here now down the street. Is there anything I can do to help you?'” Singh said.

The man did not respond and Singh left the store as quickly as possible.

He said the most effective way to help people who feel marginalised is to “be there for each other in these moments”.

A bystander who checks in with the person being harassed in any situation can make all the difference, he said.

The owner of the store told Boston.com that he was going back and forth between the back and front of the shop at the time of the incident that took place on November 11 and saw the man who spoke to Singh come in.

He said he had planned to ask the man to leave, but went to the back of the store when the incident occurred. Both Singh and the other man were gone when he returned.

He said he was shocked and sorry when his clerk told him what happened.

“I don’t know where that guy came from and I hope I don’t see him again,” said the owner, who did not want to be named.

Over 200 incidents of hateful harassment and intimidation across the US have been reported since Donald Trump won the presidential election.