Four Singaporean workers suffered burns in a fire at a chemical manufacturing plant on Jurong Island yesterday morning.

The injured men were taken to Singapore General Hospital, where one is warded in the Intensive Care Unit while the other three are in stable condition, a spokesman for the hospital said.

Of the three in stable condition, two are in the general ward and the last is in a high-dependency ward.

The Singapore Civil Defence Force (SCDF) was alerted to the incident at the Mitsui Elastomers Singapore premises at about 2.20am.

Responding to queries from The Straits Times, a spokesman for the chemical company at 701 Ayer Merbau Road said the fire was extinguished with foam by 4am, with help from the SCDF and their in-house Company Emergency Response Team.

The workers are employees of Mitsui Elastomers Singapore, a subsidiary of Japan-based Mitsui Chemicals.

They were on duty at the time of the incident, said the company spokesman.

The company manufactures high-performance polymers that are used for automotive and packaging materials.

ST understands that families of the injured have been notified.

The SCDF said the fire involved a petrochemical leak from a heat-exchanger unit within the plant.

A heat-exchanger is a device that allows heat from a liquid or gas to transfer to a second substance without the two substances mixing or coming into direct contact.

SCDF said the cause of the fire is still under investigation.