I also only heard before in the 90s....maybe I ignorant
This is what MSM says....
According to The Straits Times, Fong Hong San’s members are said to be active in Pasir Ris and their favourite hangout is Downtown East.
An ex-triad leader, 56, who declined to be named, told the same paper that the original Fong Hong San had its roots in Indonesia but moved to Singapore in the 1960s when it began betting, protection and loan shark activities first in Bukit Batok and Circuit Road before re-locating to Geylang.
He said: “But it was most famous in Circuit Road, where there were a lot of gangs. It won the turf. It was quite a big gang, 200 to 300 people.”