
In a post on its Facebook account, the Singapore Civil Defence Force (SCDF) said it was alerted to the incident at 3.35am.
A search and rescue mission comprising 60 SCDF officers was subsequently launched. K9 search dogs were also deployed to assist in the operation.
SCDF said all workers at the construction site had been accounted for as of 6.45am, adding that the injured workers were taken to the Changi General Hospital.