[Update June 14, 11.30am] The women who were arrested for causing trouble in Orchard Road have been repatriated to South Korea, the police said on Wednesday night (June 14).
They were given a stern warning and had their visit passes cancelled, the police added.
A video of the women being apprehended by police officers was posted online by Facebook user KP Lau on June 12 at about 7.08pm.
In the video, there appeared to be a skirmish and women's voices could be heard shouting as bystanders look on.
In response to Stomp media queries, the police said in a statement that the group of women were arrested under the Public Order Act along Tanglin Road at about 9.10pm.
The location is near The St Regis hotel where North Korean Leader Kim Jong Un was staying for the summit.
At the time of the incident, Mr Kim was on his way to visit Marina Bay Sands and Gardens by the Bay.
The police said that the women were actually in a "smaller, even more restricted special zone where security is even tighter because of their proximity to where the United States of America and Democratic People's Republic of Korea leaders are staying".
The police said that the same group of South Koreans were at Sentosa in the vicinity of Capella Singapore hotel earlier on the same day where they unfurled their banners to promote their cause.
The police then found them near Shangri-La Hotel, where US President Donald Trump was staying, and in possession of protest placards.
"They were warned to leave the enhanced security special event area," said the police.
However, the group did not comply with instructions from the police to leave the area and made their way to The St Regis Singapore, which is also within the special event area.
"The police again stopped and warned them not to carry out any protest activities," the statement said.
"During the engagement, they refused to cooperate with the police, became rowdy and started to shout.
"Despite police’s repeated warnings, the group continued shouting and were subsequently arrested.
"During the arrest, the group struggled and were uncooperative.
"They were found in possession of protest placards."
Police investigations are ongoing.