SINGAPORE - Two Malaysian men were arrested after bottles holding a brown liquid, suspected to contain drugs, were found in a lorry at Jurong Port.

Immigration and Checkpoints Authority (ICA) officers found four bottles of the brown liquid, believed to be kratom, in a Malaysia-registered lorry that was transporting metal beams on Dec 10.

Two other bottles containing remnants of a similar liquid were also found hidden under and behind the driver's seat, the ICA said in a Facebook post on Sunday (Dec 22).

In the post titled "No time for 'high' tea", the ICA shared photos of what appears to be carbonated drink bottles holding the brown liquid.

Kratom contains Mitragynine and 7-Hydroxymitragynine, which are Class A controlled drugs.

Anyone found guilty of importing Class A controlled drugs into Singapore will be jailed for at least five years and given at least five strokes of the cane.

They can be jailed for up to 30 years and given up to 15 strokes of the cane.

Two Malaysian men, aged 35 and 38, were arrested for their connection to the case on Dec 10, which has been referred to the Central Narcotics Bureau for further investigation, the ICA said.