SINGAPORE - Security for buses entering Singapore through Tuas Checkpoint will be stepped up in a move to fight terrorism, contraband items and stowaways.

The Immigration and Checkpoints Authority (ICA) has set up two imaging scanners that all buses will have to go through from the second half of this year.

A controlled trial began earlier this month (April) with officers travelling through the scanners with bus drivers to familiarise them with the new process, according to Assistant Commissioner (AC) Colin Tan who heads the checkpoint.

They will help officers detect modified bus compartments and explosives.

The change is not expected to extend passengers' waiting time, said AC Tan, adding: "Clearances for both bus and passengers will be conducted simultaneously... we will strive to have buses waiting for their passengers."

Currently, officers manually inspect the buses by boarding them and looking out for transgressions after passengers have alighted at the arrival hall.

The scanners will perform another layer of checks.

About 40 officers have been trained to study their X-ray images and to detect possible dangers and contraband items.

During a demonstration on Thursday (April 26), bus drivers entered the scanner through an automatic barrier that lifts after a camera captures the bus's licence number.

The bus then goes through a sensor that detects radioactive materials before moving forward to approach a control panel where the driver presses a button located near an intercom to start the scan.

A green light flashes on, and the driver drives through the scanner. Images are sent to a control room facing the scanners.

AC Tan said that the scanners will help officers conduct more targeted checks.

He added: "Some buses have modified compartments that can be hard to detect. With the X-ray images, they can know where to focus their attention."

The ICA is studying plans to implement bus scanners at Woodlands checkpoint but they may take on a different form due to space constraints.