After a drinking session with his colleagues, Alvin Kek Yoke Boon, the chief operations officer (COO) of SMRT Trains, got into his car and drove, by mistake, to the Woodlands Checkpoint, even though he had no plans to leave Singapore.
He was caught after an Immigration and Checkpoints Authority (ICA) officer noticed that he reeked of alcohol.
Kek, 51, was jailed for two weeks and fined $4,000 on Monday after he was convicted of drink driving for the second time.
He was also disqualified from driving all classes of vehicles for three years.
Responding to queries from The Straits Times, SMRT's corporate communications vice-president Margaret Teo said that Kek has been suspended from work - without giving any more details.
The court heard that Kek met some colleagues at the Temasek Club in Rifle Range Road, near Bukit Timah Road, around 11pm on April 20 for drinks. He stayed there for about three hours and drank four mugs of beer.
Deputy Public Prosecutor Teo Lu Jia said: "He stated that he was having drinks with his colleagues as his father had passed away recently, on April 14, and he also needed to de-stress."
Kek left the club at around 2.30am on April 21, got into his car and drove to the Woodlands Checkpoint, about 15km away.
He stopped his vehicle there at around 3am before telling an ICA officer he had made a mistake and had no intention of leaving Singapore.
The officer noticed that Kek smelt of alcohol, and asked him to get out of his car.
The police were notified and a test revealed he had 65 microgrammes of alcohol in 100ml of breath - almost double the prescribed limit of 35 microgrammes.
Kek joined SMRT in 2013 and was one of four former senior military men whom chief executive Desmond Kuek drafted into the company that year.
In November last year, Kek fronted the media briefing on the Joo Koon train collision, where 38 people were injured after a stalled SMRT train was hit from behind by another train.
Before he joined SMRT, Kek spent 14 years with the Singapore Armed Forces, where he was a colonel and a chief engineer officer.
During his time in the military, he was also part of the National Day Parade's organising committee six times, and headed the 2011 committee as chairman.
His first conviction for drink driving was on March 11, 2004, and he was then fined $2,800.
He was also banned from driving for two years.
First-time offenders convicted of drink driving can be jailed for up to six months or fined between $1,000 and $5,000.
Repeat offenders can be jailed for up to a year and fined between $3,000 and $10,000.
