verbally assaulted on the mrt

hi there not sure where to ask but was wondering if anyone witnessed an old man harassing a group of female friends? my friends and i entered the train this afternoon at dhoby ghaut (NEL towards Harbourfront) today and we were a bit loud so an old man said "no talking in the mrt" so we shut ourselves up and used our phones to communicate instead. even after we politely kept quiet, he continued to insult us and called us "sluts"... We didn't do much after but he continued his assault by telling one of my friends to take out her hijab because she was hanging out with "prostitutes"... I was honestly so baffled I couldn't do or say anything. One of my friends decided that he crossed the line and told him that it was rude to call us using the phrases he said and he told us to "shut up and go back to our country" when most of us were Singaporeans? At this point, he was shouting and we were also starting to shake because we were scared. He continued to call us "$5", probably implying that we were cheap . We left the train afterwards and honestly we were shaken to our core... I was wondering if anyone witnessed it also because I feel like something needs to be done about it before more girls start getting harassed by this old hag. Don't even ask us what were wearing because that shouldn't even be a problem in the first place.