Even after 10 years of experience in dealing with security incidents in Singapore's public transport system, police Staff Sergeant (SSG) Nasron Nasir had his nerves rattled when he was tasked to respond to a 999 call on April 2.
The 35-year-old had to rush to Hougang MRT station after an unattended bag was found on the platform, resulting in operator SBS Transit ordering a temporary closure and trains to bypass the stop.
Together with Special Constabulary Corporal (Cpl) Muhammad Ruzaini, 22, they were the first Public Transport Security Command (TransCom) officers to arrive at the MRT station.
"Honestly speaking, I was really nervous. I thought it was going to be the first explosives case (on the MRT) in Singapore.
"But we needed to overcome our fear and be sharp. We couldn't let our flaws cloud our judgment," SSG Nasron, a TransCom veteran, told The Straits Times in an interview with him and Cpl Ruzaini.
The bag, left behind by a 39-year- old man while he ran an errand, was later found to contain only household items.
He was arrested for causing alarm to the public after preliminary investigations showed that he had left the bag intentionally.
The incident also cast the spotlight on the work of the TransCom, which was commissioned in 2009.
TransCom had its beginnings as the Police MRT Unit, which was formed in 2005 in the light of growing global security threats and the vulnerability of the public transport system to attacks.
In July that year, terrorists struck London with coordinated bombings on three underground trains and on a bus.
The unit has grown from 30 officers to about 500 now, in tandem with the expansion of Singapore's rail network.
Full-time national servicemen such as Cpl Ruzaini account for 80 per cent of the unit's staff strength and play a vital role in patrolling the transport network daily, responding to a range of incidents, from theft to outrage of modesty and disputes.
SSG Nasron said TransCom officers are trained to know the ins and outs of each MRT station, so they can help evacuate commuters if necessary.
They also need to learn the different "characteristics" of each station, based on the crowds which frequent it at various times of the day, and the associated crime risks.
While both he and Cpl Ruzaini were unable to discuss the specifics of the April 2 case as it is under investigation, they said the general procedure would be to cordon off the area around the bag.
When dealing with suspicious items a visual assessment is first conducted.
"We look for tell-tale signs - like oil leaks, protruding cables, ticking sounds, pungent smell - signs indicating it could be dangerous," said SSG Nasron.
"We also assess (based on) whether bomb threats have been made recently," said Cpl Ruzaini.
SSG Nasron, who has 150 officers in his team, said they are asked to respond to cases of unattended bags left at MRT stations and bus interchanges "every few days".
But they are mostly false alarms, with contents of the bags ranging from towels to rotten food.
Still, SSG Nasron said: "There's always a stressful feeling when we open up a bag... But that's why we are here - to make sure the public transport system is safe."
This article was first published on April 10, 2017.
Get a copy of The Straits Times or go to straitstimes.com for more stories.