YOU'LL have a hard time getting past auxiliary police officer Arasu Kumaran, 27. If you're a crook, that is.

His primary responsibility is verifying travel documents and detecting forgeries.

Airlines hire security management firm Aetos to perform passport checks. The firm then deploys its officers to transit lounges for these duties.

Mr Arasu has been trained to detect fake passports.

With five years' experience under his belt, the no-nonsense officer knows what to look out for.

Besides scrutinising certain security features of a passport, he also looks out for suspicious behaviour such as cold sweat and shifty looks.

Mr Arasu has seen 10 to 15 such cases in three years. Most offenders are in transit in Singapore and are seeking political asylum in European countries.

If he finds any suspicious activity, Mr Arasu will contact the relevant embassy to verify the travel documents. Once he gets confirmation that the document is fraudulent, he hands the suspects over to the airport police.

Once, a woman insisted that she was from Bulgaria, but could not speak a word of the language.

Mr Arasu has developed a keen eye for tell-tale signs like these.

So far, no one has put up any resistance or tried to run away, but Mr Arasu does not take that for granted.

"Anything can happen. We have to be clear-headed and composed in every situation."

That includes dealing with drunk passengers who refuse to cooperate.

Being a security officer also means standing firm in the face of tearjerkers.

Once, he caught a foreign woman and her 5-year-old daughter with fake visas.

The girl was crying when they were being handed over to the airport police.

Mr Arasu said: "Even my female colleague was crying when that happened."

He also screens staff members who enter aircraft and checks their belongings for prohibited items such as weapons and explosives.

Duties of auxilliary police officers also include crowd control and escorting dangerous items. The job also requires working on shifts.

Every week, Mr Arasu works two days each in the morning, afternoon and night. He works six days a week, and finds the hours quite regular.

He said: "You have to be mentally prepared for everything. It's an interesting job."