A notice at a coffee shop stating that it is closed to mourn the victims of a deadly crowd crush in Seoul’s Itaewon district overnight. (Choi Jae-hee / The Korea Herald)

Restaurants and cafes near the site where over 150 people died in a fatal stampede in Seoul’s Itaewon on Saturday night will close for a three-day mourning period for the victims, a police officer said Sunday.

“Some stores have already stopped operations. Whether the temporary closure will extend depends on how the situation unfolds,” a police officer who wished to remain anonymous told The Korea Herald.

The closures are voluntary and some businesses have opened as usual.

On Saturday night, at least 151 people died in a crush as Halloween crowd surged into a narrow alleyway near the neighborhood’s landmark Hamilton Hotel. It is the deadliest mass crushing incident in South Korea's history. Officials say most of the victims were young adults in their 20s.

As of noon Sunday, many stores not located near the site of the tragedy have also temporarily closed as a gesture of respect.

Park, 41, who runs a franchise coffee shop on the other side of the district where the stampede occurred, said “there has been no disaster like this in the neighborhood over the past few years. My store is closed today."