SINGAPORE - The immigration clearance system at Tuas Checkpoint suffered disruptions for several hours from 4am on Saturday (Sept 7).

The Immigration and Checkpoints Authority (ICA) issued an advisory on Facebook at about 5am that its immigration clearance system at Tuas Checkpoint was experiencing "intermittent slowness".

It said the immigration clearance at the affected lanes progressively resumed from 7.20am.

The system returned to normal at 9.30am, more than five hours after the initial disruption.

"More resources were immediately deployed to manage the situation. Officers from the morning shift reported to work earlier, while our officers on night shift remained behind to assist in the clearance of travellers.

"ICA regrets the inconvenience caused to travellers and seeks their understanding and patience," it said.

The systems disruption caused heavy traffic in the departure and arrival zones at the checkpoint, delaying travellers.

At 6.35am, ICA also noted heavy departure traffic at Woodlands Checkpoint.

Several netizens pointed out that the heavy traffic could be due to commuters opting to use the Woodlands Checkpoint due to the disruption at Tuas Checkpoint.

On Aug 29, a localised power trip caused disruptions to the immigration clearance system at Tuas Checkpoint.

The system was disrupted at 6.45am and returned to normal at 1.30pm.

The system disruption caused heavy traffic at the arrival and departure car zones for more than six hours.