A 33-year-old man trapped on a crane died at PSA's Keppel Terminal on Wednesday morning.
The Singapore Civil Defence Force was alerted to the incident around 10.20am.
The man was standing near a cable drum of the gantry crane at the PSA Keppel Terminal carrying out checks on a gearbox, said a Ministry of Manpower spokesman.
The man was later found caught in the drum. Investigations are ongoing to establish what led to the incident. PSA Corporation has been instructed to stop all maintenance and repairs on the affected crane.
The Straits Times understands that the worker was a Singaporean.
SCDF said it sent a fire engine, a Red Rhino, an ambulance and three support vehicles to the scene. When they arrived, they found the man trapped in the cable drum on top of the crane. He was pronounced dead at the scene.
A PSA spokesman said the company is helping the family of the deceased and cooperating with the authorities in investigations.