Police reports have been lodged over a Toa Payoh hawker centre table dispute.
The police said they were looking into the matter and have asked for anyone with information to call 1800-255-0000 or submit information online at www.police.gov.sg/iwitness. They added that all information from the public would be kept confidential.
The incident, which happened at about 8.45pm last Friday, involved an elderly man and a young couple. It was filmed by a bystander, who shared the video on Facebook.
The video shows the woman shouting at the elderly man, before her male companion shoved the elderly man from behind. This apparently involved a dispute over sharing a table.
Since it was posted at around midnight on Sunday, the video has been viewed 2.5 million times, as of 7pm yesterday.
Ms Janice Lim, who was having dinner at the hawker centre last Friday, said she was sitting at a table nearby when the incident happened.
It was very crowded and the table in dispute was the only available one in the area at the time, added Ms Lim, who spoke to The Straits Times on Sunday.
The elderly man, who was holding a tray of food, asked the woman how many people were sitting at the table. The woman's reply was "can't you see it's reserved", Ms Lim said, adding that there was a foldable umbrella on the table.
The man said he could not and repeated a few times that he needed just one seat, according to Ms Lim. She added that he did not raise his voice.
He also asked the woman what she meant by "reserved", as the hawker centre was a public place, Ms Lim recounted.
The woman replied loudly: "You don't understand the word reservation?"
The young woman then told her companion that the elderly man was trying to take their table.
Shortly after, the young man shoved the elderly man from behind. The man nearly lost his balance, but managed to stay on his feet by holding on to the table.
The young man then asked him: "Why did you disturb her?"
Mr Alvin Lye, 45, who regularly dines at the hawker centre, said it can get quite crowded during Friday and weekend nights.
"But people tend to share their tables in such situations, so what happened was quite uncommon. There was no reason for the woman to be so hostile to the elderly man," he added.
Since the video went viral, netizens have tried to identify the couple.
Student Cherry Tan, 22, found herself at the centre of this incident after some netizens wrongly identified her and her boyfriend as being the couple in the video.
She released a statement on her Facebook account, which said: "I would like to take this opportunity to clarify that my boyfriend and I were never involved in the case."
Speaking to The Straits Times yesterday, she said the incident had not only hurt her but had also distressed her family and friends.
On Sunday, in response to online speculation, UOB said it was untrue that the couple worked at the bank.